NCMath 2 Unpack
NCMath 2 Unpack
NCMath 2 Unpack
North Carolina
Math 2
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North Carolina Course of Study - Math 2 Standards
Number Algebra Functions Geometry Statistics & Probability
The real number system Overview Overview Overview Overview
Extended the properties of Seeing structure in Interpreting functions Congruence Making Inference and
exponents to rational expressions Understand the concept of a Experiment with Justifying Conclusions
exponents Interpret the structure of function and use function transformations in the plane Understand and evaluate
NC.M2.N-RN.1 expressions notation NC.M1.G-CO.2 random processes underlying
NC.M2.N-RN.2 NC.M2.A-SSE.1a NC.M2.F-IF.1 NC.M1.G-CO.3 statistical experiments
Use properties of rational and NC.M2.A-SSE.1b NC.M2.F-IF.2 NC.M1.G-CO.4 NC.M1.S-IC.2
irrational numbers NC.M2.A-SSE.3 Interpret functions that arise NC.M1.G-CO.5
NC.M2.N-RN.3 in applications in terms of a Understand congruence in Conditional probability and
Perform arithmetic context terms of rigid motions the rules for probability
The complex number system operations on polynomials NC.M2.F-IF.4 NC.M1.G-CO.6 Understand independence and
Defining complex numbers Perform arithmetic operations Analyze functions using NC.M1.G-CO.7 conditional probability and
NC.M2.N-CN.1 on polynomials different representations NC.M1.G-CO.8 use them to interpret data
NC.M2.A-APR.1 NC.M2.F-IF.7 Prove geometric theorems NC.M1.S-CP.1
NC.M2.F-IF.8 NC.M1.G-CO.9 NC.M1.S-CP.3a
Creating equations NC.M2.F-IF.9 NC.M1.G-CO.10 NC.M1.S-CP.3b
Create equations that describe NC.M1.S-CP.4
numbers or relationships Building functions Similarity, right triangles, NC.M1.S-CP.5
NC.M2.A-CED.1 Build a function that models a and trigonometry Use the rules of probability to
NC.M2.A-CED.2 relationship between two Understand similarity in terms compute probabilities of
NC.M2.A-CED.3 quantities of similarity transformations compound events in a uniform
NC.M2.A-CED.4 NC.M2.F-BF.1 NC.M1.G-SRT.1a probability model
Build new functions from NC.M1.G-SRT.1b NC.M1.S-CP.6
Reasoning with equations existing functions NC.M1.G-SRT.1c NC.M1.S-CP.7
and inequalities NC.M2.F-BF.3 NC.M1.G-SRT.1d NC.M1.S-CP.8
Understand solving equations NC.M1.G-SRT.2a
as a process of reasoning and NC.M1.G-SRT.2b
explain the reasoning NC.M1.G-SRT.3
NC.M2.A-REI.1 Prove theorems involving
NC.M2.A-REI.2 similarity
Solve equations and NC.M1.G-SRT.4
inequalities in one variable Define trigonometric ratios
NC.M2.A-REI.4a and solve problems involving
NC.M2.A-REI.4b right triangles
Solve systems of equations NC.M1.G-SRT.6
NC.M2.A-REI.7 NC.M1.G-SRT.8
Represent and solve equations NC.M1.G-SRT.12
and inequalities graphically
NC.M2.A-REI.11
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Number – The Real Number System
NC.M2.N-RN.1
Extend the properties of exponents to rational exponents.
Explain how expressions with rational exponents can be rewritten as radical expressions.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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Number – The Real Number System
NC.M2.N-RN.2
Extend the properties of exponents to rational exponents.
Rewrite expressions with radicals and rational exponents into equivalent expressions using the properties of exponents.
3
Students should be able to rewrite expressions Example: Write √27𝑥 2 𝑦 6 𝑧 3 as an expression with rational exponents.
2
involving radicals as expressions using rational Example: Write an equivalent exponential expression for 83 ? Explain how they are equivalent.
exponents and use the properties of exponents to 2 1 1 2
simplify the expressions. Solution: 83 = (82 )3 = (83 ) = 22 In the first expression, the base number is 8 and the exponent is 2/3. This
means that the expression represents 2 of the 3 equal factors whose product is 8, thus the value is 4, since
Students should be able to explain their (2 × 2 × 2) = 8; there are three factors of 2; and two of these factors multiply to be 4. In the second
reasoning while simplifying expressions with expression, there are 2 equal factors of 8 or 64. The exponent 1/3 represents 1 of the 3 equal factors of 64.
rational exponents and radicals. Since 4 × 4 × 4 = 64 then one of the three factors is 4. The last expression there is 1 of 3 equal factors of 8
which is 2 since 2 × 2 × 2 = 8. Then there are 2 of the equal factors of 2, which is 4.
3 3
4 4
Example: Given 814 = √813 = ( √81) , which form would be easiest to calculate without using a calculator. Justify
your answer?
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Example: Determine whether each equation is true or false using the properties of exponents. If false, describe at
least one way to make the math statement true.
5
a. √32 = 22
3
b. 162 = 82
1
4
c. 42 = √64
3 6
d. 28 = ( √16)
1 1
e. (√64)3 = 86
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Number – The Real Number System
NC.M2.N-RN.3
Use properties of rational and irrational numbers.
Use the properties of rational and irrational numbers to explain why:
the sum or product of two rational numbers is rational;
the sum of a rational number and an irrational number is irrational;
the product of a nonzero rational number and an irrational number is irrational.
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Number – The Complex Number System
NC.M2.N-CN.1
Defining complex numbers.
Know there is a complex number i such that 𝑖 2 = – 1, and every complex number has the form 𝑎 + 𝑏𝑖 where 𝑎 and 𝑏 are real numbers.
Students should be able to define a complex number and identify when they are likely
to use them.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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and that the square root of a negative number is a
complex number.
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Algebra, Functions & Function Families
NC Math 1 NC Math 2 NC Math 3
Note: The Numbers conceptual category also relates to the Algebra and Functions conceptual categories. As students become more fluent
with their work within particular function families, they explore more of the number system. For example, as students continue the study of
quadratic equations and functions in Math 2, they begin to explore the complex solutions. Additionally, algebraic manipulation within the
real number system is an important skill to creating equivalent expressions from existing functions.
Back to: Table of Contents
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Algebra – Seeing Structure in Expressions
NC.M2.A-SSE.1a
Interpret the structure of expressions.
Interpret expressions that represent a quantity in terms of its context.
a. Identify and interpret parts of a quadratic, square root, inverse variation, or right triangle trigonometric expression, including terms, factors,
coefficients, radicands, and exponents.
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variation, or right triangle trigonometric Example: Ohm’s Law explains the relationship between current, resistance, and voltage. To determine the current
expressions. 𝑉
passing through a conductor you would need to evaluate the expression , where V represents voltage and R represents
𝑅
resistance. If the resistance is increased, what must happen to the voltage so that the current passing through the
conductor remains constant?
𝑦
Example: The tangent ratio is where (𝑥, 𝑦) is a coordinate on the terminal side of the angle in standard position. Use
𝑥
the diagram to justify why the tangent of 45° is always 1. Then, expand that reasoning to justify why every individual
angle measure has exactly one value for tangent.
Use similar reasoning to justify why every angle has exactly one value of sine and one value of cosine.
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Algebra – Seeing Structure in Expressions
NC.M2.A-SSE.1b
Interpret the structure of expressions.
Interpret expressions that represent a quantity in terms of its context.
b. Interpret quadratic and square root expressions made of multiple parts as a combination of single entities to give meaning in terms of a
context.
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a. Describe what you are finding when you calculate 𝑥 − 𝜇.
b. Describe how the formula for standard deviation is similar to the formula for finding mean.
c. What part of the radicand would have to increase so that the value of the standard deviation would also
increase: the numerator (∑(𝑥 − 𝜇)2 ) or the denominator (n)? Justify your answer.
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Algebra – Seeing Structure in Expressions
NC.M2.A-SSE.3
Interpret the structure of expressions.
Write an equivalent form of a quadratic expression by completing the square, where 𝑎 is an integer of a quadratic expression, 𝑎𝑥 2 + 𝑏𝑥 + 𝑐, to
reveal the maximum or minimum value of the function the expression defines.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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Seeing Dots (Illustrative Mathematics)
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Algebra – Arithmetic with Polynomial Expressions
NC.M2.A-APR.1
Perform arithmetic operations on polynomials.
Extend the understanding that operations with polynomials are comparable to operations with integers by adding, subtracting, and multiplying
polynomials.
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Algebra – Creating Equations
NC.M2.A-CED.1
Create equations that describe numbers or relationships.
Create equations and inequalities in one variable that represent quadratic, square root, inverse variation, and right triangle trigonometric
relationships and use them to solve problems.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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Example: Jamie is selling key chains that he has made to raise money for school trip. He has done a little research and found that the
expression −20𝑥 + 140 represents the number of keychains that he will be able to sell, given that x represents the price of one
keychain. Each key chain costs Jamie $.50 to make. Write and solve an inequality that he can use to determine the range of prices he
could charge make sure that he earns at least $150 in profit.
Example: In kickboxing, it is found that the force, f, needed to break a board, varies inversely with the length, l, of the board. Write
and solve an equation to answer the following question:
If it takes 5 lbs. of pressure to break a board 2 feet long, how many pounds of pressure will it take to break a board that is 6 feet
long?
Example: To be considered a ‘fuel efficient’ vehicle, a car must get more than 30 miles per gallon. Consider a test run of 200 miles.
How many gallons of fuel can a car use and be considered ‘fuel-efficient’?
Example: The centripetal force 𝐹 exerted on a passenger by a spinning amusement park ride is related to the number of seconds 𝑡
155𝜋2
the ride takes to complete one revolution by the equation 𝑡 = √ . Write and solve an equation to find the centripetal force
𝐹
exerted on a passenger when it takes 12 seconds for the ride to complete one revolution.
Example: John has a 20-foot ladder leaning against a wall. If the height of the wall that the ladder needs to
reach is at least 15ft, create and solve an inequality to find the angle the ladder needs to make with the
ground.
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Algebra – Creating Equations
NC.M2.A-CED.2
Create equations that describe numbers or relationships.
Create and graph equations in two variables to represent quadratic, square root and inverse variation relationships between quantities.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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Algebra – Creating Equations
NC.M2.A-CED.3
Create equations that describe numbers or relationships.
Create systems of linear, quadratic, square root, and inverse variation equations to model situations in context.
This standard should be connected with Example: The FFA has $2400 in a fund to raise money for a new tractor. They are selling trees and have determined
NC.M2.A-REI.7 where students solve and 2400
that the number of trees they can buy to sell depends on the price of the tree p, according to the function 𝑛(𝑝) = .
interpret systems and with NC.M2.A-REI.11 𝑝
where students understand the representation of Also, after allowing for profit, the number of trees that customers will purchase depends on the price which the group
the solutions of systems graphically. purchased the trees with function 𝑐(𝑝) = 300 − 6𝑝. For what price per tree will the number of trees that can be equal
the number of trees that will be sold?
Example: Susan is designing wall paper that is made of several different sized squares. She is using a drawing tool for
the square where she can adjust the area and the computer program automatically adjusts the side length by using the
formula 𝑠 = √𝐴. The perimeter of the square can also be inputted into the computer so that the computer will
𝑃
automatically adjust the side length with the formula 𝑠 = . Susan wants to see what the design would look like if the
4
perimeter and area of one of the squares was the same. Create a system of equations that Susan could solve so that she
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Mastering the Standard
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knows what to input into the computer to see her design. What is the side length that produces the same area and
perimeter?
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Algebra – Creating Equations
NC.M2.A-REI.1
Understand solving equations as a process of reasoning and explain the reasoning.
Justify a chosen solution method and each step of the solving process for quadratic, square root and inverse variation equations using mathematical
reasoning.
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choose to square both sides, solve by Example: If a, b, c, and d are real numbers, explain how to solve how to solve 𝑎𝑥 2 + 𝑏𝑥 + 𝑐 = 𝑑 in 2 different methods. Discuss
graphing or with a table. the pros and cons of each method.
Students should be able to chose and justify solution Method A Method B
Discussions on the solving processes methods. 2
5𝑥 + 10 = 90 5𝑥 2 + 10 = 90
and the benefits and drawbacks of Example: To the right are two methods for
−10 = −10 −90 = −90
each method should lead students to solving the equation 5𝑥 2 + 10 = 90. Select one 2 2
not rely on one solving process. of the solution methods and construct a viable 5𝑥 = 80 5𝑥 − 80 = 0
2 2
Students should make determinations argument for the use of the method. 5𝑥 80 5(𝑥 − 16) = 0
=
on the solving process based on the 5 5 5(𝑥 + 4)(𝑥 − 4) = 0
context of the problem, the nature and 𝑥 2 = 16 𝑥 + 4 = 0 𝑜𝑟 𝑥 − 4 = 0
structure of the equation, and 𝑥 = ±√16 𝑥 = 4 𝑜𝑟 𝑥 = −4
efficiency.
𝑥 = 4 𝑜𝑟 𝑥 = −4
While solving algebraically, students
need to use the properties of equality
Method A Method B
to justify and explain each step Example: To the right are two methods for
2𝑥 2 − 3𝑥 + 4 = 0 2𝑥 2 − 3𝑥 + 4 = 0
obtained from the previous step, solving the equation 2𝑥 2 − 3𝑥 + 4 = 0.
assuming the original equation has a Select one of the solution methods and 3
3 ± √(−3)2 − 4(2)(4) 𝑥2 − 𝑥 + 2 = 0
solution. construct a viable argument for the use of 𝑥= 2
the method. 2(2) 3 9 9
Students need to solve quadratic, 𝑥2 − 𝑥 + = −2 +
2 16 16
square root and inverse variation 3 ± √−23
equations. 𝑥= 3 2 −23
4 (𝑥 − ) =
4 16
3 ± 𝑖√23
𝑥= 3 −23
4 𝑥− = ±√
4 16
3 𝑖√23
𝑥= ± 3 𝑖√23
4 4 𝑥= ±
4 4
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Algebra – Reasoning with Equations and Inequalities
NC.M2.A-REI.2
Understand solving equations as a process of reasoning and explain the reasoning.
Solve and interpret one variable inverse variation and square root equations arising from a context, and explain how extraneous solutions may be
produced.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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Students should understand that the process of algebraically 𝑑
Example: The relationship between rate, distance and time can be calculated with the equation 𝑟 = ,
𝑡
solving an equation can produce extraneous solutions.
where 𝑟 is the rate (speed), 𝑑 represents the distance traveled, and 𝑡 represents the time. If the speed of a
Students study this in Math 2 in connection mainly to square
wave from a tsunami is 150 m/s and the distance from the disturbance in the ocean to the shore is 35
root functions. When teaching this standard, it will be
kilometers, how long will it take for the wave to reach the shore?
important to link to the concept of having a limited domain,
not only by the context of a problem, but also by the nature of
Students should be able to solve square root equations and identify extraneous solutions.
the equation.
Example: Solve algebraically: √𝑥 − 1 = 𝑥 − 7
Interpret solutions in terms of the context. a) Now solve by graphing.
b) What do you notice?
c) Check the solutions in the original equation.
d) Why was an “extra” answer produced?
Example: The speed of a wave during a tsunami can be calculated with the formula 𝑠 = √9.81𝑑 where
𝑠 represents speed in meters per second, 𝑑 represents the depth of the water in meters where the
disturbance (for example earthquake) takes place, and 9.81 m/s2 is the acceleration due to gravity. If the
speed of the wave is 150 m/s, what is depth of the water where the disturbance took place?
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Algebra – Reasoning with Equations and Inequalities
NC.M2.A-REI.4a
Solve equations and inequalities in one variable.
Solve for all solutions of quadratic equations in one variable.
a. Understand that the quadratic formula is the generalization of solving 𝑎𝑥 2 + 𝑏𝑥 + 𝑐 by using the process of completing the square.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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Students who write vertex form first left column, provide a mathematical reason for each step as you have done before. (Refer back to a visual model as
−2𝑥 2 − 16𝑥 − 20 = 0 needed.) One the right side, identify how you can see that mathematical reasoning in the generalized form. When
−2(𝑥 2 − 8𝑥) − 20 = 0 complete, try out the new formula with the example problem from the left column.
−2(𝑥 2 − 8𝑥 + 16) − 20 − 32 = 0
Completing the Square Completing the Square
−2(𝑥 − 4)2 − 52 = 0
(Example) (Generalized)
−2(𝑥 − 4)2 = 52
3𝑥 2 + 5𝑥 + 4 = 0 𝑎𝑥 2 + 𝑏𝑥 + 𝑐 = 0
(𝑥 − 4)2 = 26
𝑥 − 4 = ±√26 5 4 𝑏 𝑐
𝑥2 + 𝑥 + = 0 𝑥2 + 𝑥 + = 0
𝑥 = 4 ± √26 3 3 𝑎 𝑎
5 52 52 4 𝑏 𝑏2 𝑏2 𝑐
Students who adapts method 𝑥2 + 𝑥 + 2 2 = 2 2 − 𝑥2 + 𝑥 + 2 2 = 2 2 −
3 2 ∙3 2 ∙3 3 𝑎 2 ∙𝑎 2 ∙𝑎 𝑎
−2(𝑥 2 − 8𝑥) = 20
5 25 25 4 𝑏 𝑏2 𝑏2 𝑐
−2(𝑥 2 − 8𝑥 + 16) = 20 + 32 𝑥2 + 𝑥 + = − 𝑥2 + 𝑥 + = −
−2(𝑥 − 4)2 = 52 3 36 36 3 𝑎 4 ∙ 𝑎2 4 ∙ 𝑎2 𝑎
(𝑥 − 4)2 = 26 5 25 25 4 12 𝑏 𝑏2 𝑏2 𝑐 4𝑎
𝑥2 + 𝑥 + = − ∙ 𝑥2 + 𝑥 + = − ∙
𝑥 − 4 = ±√26 3 36 36 3 12 𝑎 4∙𝑎 2 4∙𝑎 2 𝑎 4𝑎
𝑥 = 4 ± √26 5 25 −23
𝑥2 + 𝑥 + = 𝑏 𝑏2 𝑏 2 − 4𝑎𝑐
3 36 36 𝑥2 + 𝑥 + 2
=
This standard is about understanding that the 𝑎 4∙𝑎 4 ∙ 𝑎2
quadratic formula is derived from the process of 5 2 −23 𝑏 2 𝑏 2 − 4𝑎𝑐
(𝑥 + ) = (𝑥 + ) =
completing the square. Students should become 6 36 2𝑎 4 ∙ 𝑎2
very familiar with this process before introducing
the quadratic formula. Students should 5 −23
𝑥+ = ±√ 𝑏 𝑏 2 − 4𝑎𝑐
understand completing the square both visually 6 36 𝑥+ = ±√
and symbolically. Algebra titles are a great way 2𝑎 4 ∙ 𝑎2
for students to understand the reasoning behind −5 √−23
𝑥= ± −𝑏 √𝑏 2 − 4𝑎𝑐
the process of completing the square. 6 6 𝑥= ±
It is not the expectation for students to memorize 2𝑎 2𝑎
the steps in deriving the quadratic formula. −5 ± 𝑖√23
𝑥= −𝑏 ± √𝑏 2 − 4𝑎𝑐
(Remember that students have no experience with 6 𝑥=
2𝑎
rational expressions which is required as part of
completing the derivation on their own!)
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Algebra – Reasoning with Equations and Inequalities
NC.M2.A-REI.4b
Solve equations and inequalities in one variable.
Solve for all solutions of quadratic equations in one variable.
b. Explain when quadratic equations will have non-real solutions and express complex solutions as 𝑎 ± 𝑏𝑖 for real numbers 𝑎 and 𝑏.
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𝑏 2 − 4𝑎𝑐 < 0 2 Does not Example: Ryan used the quadratic formula to solve an equation and his result was
complex intersect x-axis 8±√(−8)2 −4(1)(−2)
𝑥= .
solutions 2(1)
a) Write the quadratic equation Ryan started with in standard form.
b) What is the nature of the roots?
c) What are the x-intercepts of the graph of the corresponding quadratic
function?
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Algebra – Reasoning with Equations and Inequalities
NC.M2.A-REI.7
Solve systems of equations.
Use tables, graphs, and algebraic methods to approximate or find exact solutions of systems of linear and quadratic equations, and interpret the
solutions in terms of a context.
Example: The student council is planning a dance for their high school. They did some research and found that the relationship
between the ticket price and income that they will receive from the dance can be modeled by the function 𝑓(𝑥) =
−100(𝑥 − 4)2 + 1500. They also calculated their expenses and found that their expenses can be modeled by the function
𝑔(𝑥) = 300 + 10𝑥. What ticket price(s) could the student council charge for the dance if they wanted to break-even (the
expenses are equal to the income)? Demonstrate how you can find the answer using algebraic methods, a table and with a
graph.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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Algebra – Reasoning with Equations and Inequalities
NC.M2.A-REI.11
Represent and solve equations and inequalities graphically
Extend the understanding that the 𝑥-coordinates of the points where the graphs of two square root and/or inverse variation equations 𝑦 =
𝑓(𝑥) and 𝑦 = 𝑔(𝑥) intersect are the solutions of the equation 𝑓(𝑥) = 𝑔(𝑥) and approximate solutions using graphing technology or successive
approximations with a table of values.
Students should be able to discuss how technology impacts their ability to solve more
complex equations or unfamiliar equation types.
New Vocabulary: inverse variation, constant of proportionality
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Algebra, Functions & Function Families
NC Math 1 NC Math 2 NC Math 3
Note: The Numbers conceptual category also relates to the Algebra and Functions conceptual categories. As students become more fluent
with their work within particular function families, they explore more of the number system. For example, as students continue the study of
quadratic equations and functions in Math 2, they begin to explore the complex solutions. Additionally, algebraic manipulation within the
real number system is an important skill to creating equivalent expressions from existing functions.
Back to: Table of Contents
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Functions – Interpreting Functions
NC.M2.F-IF.1
Understand the concept of a function and use function notation.
Extend the concept of a function to include geometric transformations in the plane by recognizing that:
the domain and range of a transformation function f are sets of points in the plane;
the image of a transformation is a function of its pre-image.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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Example: Using the graph below, if this transformation was written as a function, identify the domain and range.
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Functions – Interpreting Functions
NC.M2.F-IF.2
Understand the concept of a function and use function notation.
Extend the use of function notation to express the image of a geometric figure in the plane resulting from a translation, rotation by multiples of 90
degrees about the origin, reflection across an axis, or dilation as a function of its pre-image.
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Functions – Interpreting Functions
NC.M2.F-IF.4
Interpret functions that arise in applications in terms of the context.
Interpret key features of graphs, tables, and verbal descriptions in context to describe functions that arise in applications relating two quantities,
including: domain and range, rate of change, symmetries, and end behavior.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Mastering the Standard
Comprehending the Standard Assessing for Understanding
Example: The graph to the right is the voltage, v, in a given circuit as a
Connect this standard with NC.M2.F-IF.7. This function of the the time (in seconds). What was the maximum voltage and
standard focuses on interpretation from various for how long did it take to complete the circuit?
representations whereas NC.M2.F-IF.7 focuses
on generating different representations. Also,
this standard is not limited by function type and
can include functions that students do not have
the algebraic skills to manipulate. NC.M2.F-IF.7
lists specific function types for which students
can use algebra to analyze key features of the
function.
Instructional Resources
Tasks Additional Resources
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Functions – Interpreting Functions
NC.M2.F-IF.7
Analyze functions using different representations.
Analyze quadratic, square root, and inverse variation functions by generating different representations, by hand in simple cases and using
technology for more complicated cases, to show key features, including: domain and range; intercepts; intervals where the function is increasing,
decreasing, positive, or negative; rate of change; maximums and minimums; symmetries; and end behavior.
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2
of change; maximums and minimums; Example: Represent the function 𝑓(𝑥) = with a table and graph. Identify the following key features: domain and
𝑥
symmetries; and end behavior.
range; intercepts; intervals where the function is increasing, decreasing, positive, or negative; rate of change; maximums
and minimums; symmetries; and end behavior.
In Math 2 students should focus on quadratic,
square root, and inverse variation functions.
Instructional Resources
Tasks Additional Resources
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Functions – Interpreting Functions
NC.M2.F-IF.8
Analyze functions using different representations.
Use equivalent expressions to reveal and explain different properties of a function by developing and using the process of completing the square to
identify the zeros, extreme values, and symmetry in graphs and tables representing quadratic functions, and interpret these in terms of a context.
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Students should be able to identify the key features able to be found in each form of a quadratic function.
Example: Which of the following equations could describe the function of the given
graph to the right? Explain.
𝑓1 (𝑥) = (𝑥 + 12)2 + 4 𝑓5 (𝑥) = −4(𝑥 + 2)(𝑥 + 3)
𝑓2 (𝑥) = −(𝑥 − 2)2 − 1 𝑓6 (𝑥) = (𝑥 + 4)(𝑥 − 6)
2
𝑓3 (𝑥) = (𝑥 + 18) − 40 𝑓7 (𝑥) = (𝑥 − 12)(−𝑥 + 18)
2
𝑓4 (𝑥) = (𝑥 + 12) + 4 𝑓8 (𝑥) = (20 − 𝑥)(30 − 𝑥)
Instructional Resources
Tasks Additional Resources
Throwing Horseshoes (Illustrative Mathematics)
FAL: Representing Quadratics Graphically (Mathematics Assessment Project)
Profit of a Company (Illustrative Mathematics)
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Functions – Interpreting Functions
NC.M2.F-IF.9
Analyze functions using different representations.
Compare key features of two functions (linear, quadratic, square root, or inverse variation functions) each with a different representation
(symbolically, graphically, numerically in tables, or by verbal descriptions).
Example: Compare and contrast the end behavior and symmetries of the two functions represented below.
𝑥 𝑓(𝑥)
-2 4
-1 1
0 0
1 1
2 4
Instructional Resources
Tasks Additional Resources
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Functions – Building Functions
NC.M2.F-BF.1
Build a function that models a relationship between two quantities.
Write a function that describes a relationship between two quantities by building quadratic functions with real solution(s) and inverse variation
functions given a graph, a description of a relationship, or ordered pairs (include reading these from a table).
Students should be able to justify their chosen model with mathematical reasoning.
New Vocabulary: inverse variation, constant of proportionality
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Mastering the Standard
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substituting the x-intercpets for 𝑚 and 𝑛, and the
𝑥 and 𝑦 coordinates from the point for 𝑥 and
𝑓(𝑥). Once the student has solved for 𝑎 they can Example: Write an equation of the function given the graph.
plug 𝑎, 𝑚, and 𝑛 into the equation so that their
equation is written in factored form.
Instructional Resources
Tasks Additional Resources
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Functions – Building Functions
NC.M2.F-BF.3
Build new functions from existing functions.
Understand the effects of the graphical and tabular representations of a linear, quadratic, square root, and inverse variation function f with 𝑘 ∙ 𝑓(𝑥),
𝑓(𝑥) + 𝑘, 𝑓(𝑥 + 𝑘) for specific values of 𝑘 (both positive and negative).
Students should understand how changes in the Example: Describe the effect of varying the parameters 𝑎, ℎ, and 𝑘 on the shape and position of the graph of the
equation effect changes in graphs and tables of equation𝑓 (𝑥) = 𝑎 (𝑥 − ℎ) 2 + 𝑘. Then compare that to the effect of varying the parameters 𝑎, ℎ, and 𝑘 on the shape
values. and position of the graph of the equation 𝑔(𝑥) = 𝑎√𝑥 − ℎ + 𝑘.
𝑘 ∙ 𝑓(𝑥) If 0 < 𝑘 < 1 there is a vertical
compression meaning that the outputs of the
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Mastering the Standard
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function have been reduced since they were Example: Describe the transformation that took place with the function transformation where 𝑓(𝑥) = √𝑥 is transformed
multiplied by a number between 0 and 1. If to 𝑔(𝑥) = 2√𝑥 + 3 − 4.
𝑘 > 1 there is a vertical stretch meaning
that the outputs have all been multiplied by 1
Example: Write an equation for the transformation of 𝑓(𝑥) = after it has been translated 3 units to the right and reflected
the same value. If 𝑘 is negative, then all of 𝑥
the outputs will change signs and this will over the x-axis.
result in a reflection over the x-axis.
𝑓(𝑥) + 𝑘 If 𝑘 is positive all of the outputs Example: A computer game uses functions to simulate the paths of an archer’s arrows. The x-axis represents the level
are being increased by the same value and ground on which the archer stands, and the coordinate pair (2,5) represents the top of a castle wall over which he is
the graph of the function will move up. If 𝑘 trying to fire an arrow.
is negative, all of the outputs are being In response to user input, the first arrow followed a path defined by the function 𝑓(𝑥) = 6 − 𝑥 2 failing to clear the castle
decreased by the same value and the graph wall.
of the function will move down.
The next arrow must be launched with the same force and
𝑓(𝑥 + 𝑘) If 𝑘 is positive then all of the
trajectory, so the user must reposition the archer in order for
inputs are increasing by the same value.
his next arrow to have any chance of clearing the wall.
Since they are increasing before they are
plugged into the operations of the function,
the graph will move to the left. If 𝑘 is a) How much closer to the wall must the archer stand in order
negative, then all of the inputs are for the arrow to clear the wall by the greatest possible
decreasing by the same value. Since they distance?
are decreasing before they are plugged into b) What function must the user enter in order to accomplish
the operations of the function the graph will this?
move to the right. c) If the user can only enter functions of the form 𝑓(𝑥 + 𝑘),
what are all the values of k that would result in the arrow
Students should focus on linear, quadratic, clearing the castle wall?
square root, and inverse variation functions in https://www.illustrativemathematics.org/content-
this course. standards/HSF/BF/B/3/tasks/695
Instructional Resources
Tasks Additional Resources
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Geometry
NC Math 1 NC Math 2 NC Math 3
Analytic & Euclidean
Focus on coordinate geometry Focus on triangles Focus on circles and continuing the work
• Distance on the coordinate plane • Congruence with triangles
• Midpoint of line segments • Similarity • Introduce the concept of radian
• Slopes of parallel and perpendicular lines • Right triangle trigonometry • Angles and segments in circles
• Prove geometric theorems algebraically o Special right triangles • Centers of triangles
• Parallelograms
A Progression of Learning
Integration of Algebra and Geometry Geometric proof and SMP3 Geometric Modeling
• Building off of what students know from • An extension of transformational • Connecting analytic geometry, algebra,
th th
5 – 8 grade with work in the geometry concepts, lines, angles, and functions, and geometric measurement to
coordinate plane, the Pythagorean triangles from 7th and 8th grade modeling.
theorem and functions. mathematics. • Building from the study of triangles in
• Students will integrate the work of • Connecting proportional reasoning from Math 2, students will verify the properties
algebra and functions to prove geometric 7th grade to work with right triangle of the centers of triangles and
theorems algebraically. trigonometry. parallelograms.
• Algebraic reasoning as a means of proof • Students should use geometric reasoning
will help students to build a foundation to prove theorems related to lines, angles,
to prepare them for further work with and triangles.
geometric proofs.
It is important to note that proofs here are not limited
to the traditional two-column proof. Paragraph, flow
proofs and other forms of argumentation should be
encouraged.
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Geometry – Congruence
NC.M2.G-CO.2
Experiment with transformations in the plane.
Experiment with transformations in the plane.
Represent transformations in the plane.
Compare rigid motions that preserve distance and angle measure (translations, reflections, rotations) to transformations that do not preserve
both distance and angle measure (e.g. stretches, dilations).
Understand that rigid motions produce congruent figures while dilations produce similar figures.
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Transformations that are rigid (preserve distance and angle
measure: reflections, rotations, translations, or combinations of Example: Transform 𝛥𝐴𝐵𝐶 with vertices 𝐴 (1,1), 𝐵 (6,3) and 𝐶 (2,13) using the function rule
these) and those that are not (stretches, dilations or rigid motions (𝑥, 𝑦) (−𝑦, 𝑥). Describe the transformation as completely as possible.
followed by stretches or dilations). Translations, rotations and
reflections produce congruent figures while dilations produce
similar figures.
Instructional Resources
Tasks Additional Resources
Horizontal Stretch of the Plane (Illustrative Mathematics) Transforming 2D Figures (Mathematics Assessment Project)
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Geometry – Congruence
NC.M2.G-CO.3
Experiment with transformations in the plane.
Given a triangle, quadrilateral, or regular polygon, describe any reflection or rotation symmetry i.e., actions that carry the figure onto itself. Identify
center and angle(s) of rotation symmetry. Identify line(s) of reflection symmetry. Represent transformations in the plane.
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Students can describe and illustrate the center of rotation and angle(s) of rotation symmetry and line(s) of reflection
symmetry.
Instructional Resources
Tasks Additional Resources
Transforming 2D Figures (Mathematics Assessment Project)
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Geometry – Congruence
NC.M2.G-CO.4
Experiment with transformations in the plane.
Verify experimentally properties of rotations, reflections, and translations in terms of angles, circles, perpendicular lines, parallel lines, and line
segments.
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rotation are congruent and form an angle Example: Quadrilateral A’B’C’D’ is a reflection of quadrilateral ABCD Productive answers:
equal to the angle of rotation. across the given line. Draw line segments connecting A to A’ and C to C’. ̅̅̅̅̅ ∥ 𝐶𝐶′
𝐴𝐴′ ̅̅̅̅̅
Label the points of intersection with the line of reflection as E and F. What ̅̅̅̅ ≅ 𝐴
𝐴𝐸 ̅̅̅̅̅
′𝐸
There are two approaches – both that should be do you notice? ̅̅̅̅
𝐶𝐹 ≅ 𝐶′𝐹̅̅̅̅̅
used when teaching this standard. First, work ̅̅̅̅̅
𝐴𝐴′ ⊥ ̅̅̅̅
𝐸𝐹
with transformations on the coordinate plane. ̅̅̅̅̅
𝐶𝐶′ ⊥ ̅̅̅̅
𝐸𝐹
For this, students need to have some reasoning A and A’ are equidistant from the
skills with figures on the coordinate plane. line of reflection.
Calculating distances on the coordinate plane C and C’ are equidistant from the
line of reflection.
can help achieve this:
show that the line of symmetry bisects the
segment connecting image to preimage for
a reflection;
show that the segments connecting the E
image to center and preimage to center are
the same length and represent the radius of
the circle whose central angle is the angle F
of rotation
show line segments are parallel for
translations Example: Triangle 𝐴’𝐵’𝐶’ is a rotation of
show line segments are perpendicular for triangle 𝐴𝐵𝐶. Describe the rotation,
reflection indicating center, angle, and direction. Draw line segments connecting
corresponding vertices to the center. What do you notice?
The second approach is to work with the
Triangle ABC is rotated 90 CW around
transformations on the Euclidean plane. point D.
Students should use tools (patty paper, mirrors, Corresponding vertices lie on the same
rulers, protractors, string, technology, etc) to circle. The circles all have center D.
measure and reason. ̅̅̅̅ ≅ ̅̅̅̅̅
𝐶𝐷 𝐶 ′ 𝐷 and 𝑚∠𝐶𝐷𝐶 ′ = 90°.
𝐴𝐷 ≅ ̅̅̅̅̅
̅̅̅̅ 𝐴′ 𝐷 and 𝑚∠𝐴𝐷𝐴′ = 90°.
̅̅̅̅
𝐵𝐷 ≅ 𝐵 ̅̅̅̅̅
′ 𝐷 and 𝑚∠𝐵𝐷𝐵 ′ = 90°.
Instructional Resources
Tasks Additional Resources
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Geometry – Congruence
NC.M2.G-CO.5
Experiment with transformations in the plane.
Given a geometric figure and a rigid motion, find the image of the figure. Given a geometric figure and its image, specify a rigid motion or
sequence of rigid motions that will transform the pre-image to its image.
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In 8th grade, students build an understanding of Students transform a geometric figure given a rotation, reflection, or translation, using graph paper, tracing paper and/or
congruence through translations, reflections geometry software.
and rotation informally and in terms of Example: Using the figure on the right:
coordinates. Students in MS verify that images Part 1: Draw the shaded triangle after:
transformed in the plane with rigid motions a. It has been translated −7 units horizontally and +1 units
keep the same property as the preimage. They vertically. Label your answer A.
also note the effect of the rigid motion on the b. It has been reflected over the x-axis. Label your answer B.
coordinates of the image and preimage. This c. It has been rotated 90° clockwise about the origin. Label
standard extends the work in MS by requiring your answer C.
students to give precise descriptions of d. It has been reflected over the line 𝑦 = 6. Label your answer
sequences of rigid motions where they specify D.
exact points, lines and angles with coordinates
and/or equations. Analytically, each rigid
motion should be specified as follows:
For each rotation, students should specify
a point (𝑥, 𝑦) and angle.
For each translation, specific pairs of
points (𝑥, 𝑦) should be identified;
For each reflection, the equation of the Students predict and verify the sequence of transformations (a composition) that will map a figure onto another.
line (𝑦 = 𝑚𝑥 + 𝑏) should be identified. Part 2: Describe fully the transformation or sequence of transformations that:
a. Takes the shaded triangle onto the triangle labeled E.
These specificities hold true whether working b. Takes the shaded triangle onto the triangle labeled F.
in the coordinate or Euclidean plane. Students
must specify all points, lines of
reflection/symmetry and angles of rotation.
Instructional Resources
Tasks Additional Resources
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Geometry – Congruence
NC.M2.G-CO.6
Understand congruence in terms of rigid motions.
Determine whether two figures are congruent by specifying a rigid motion or sequence of rigid motions that will transform one figure onto the
other.
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Students determine if two figures are congruent by determining if rigid motions will map one figure onto the other.
Example: Determine if the figures are congruent. If so, describe and
demonstrate a sequence of rigid motions that maps one figure onto the
other.
Instructional Resources
Tasks Additional Resources
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Geometry – Congruence
NC.M2.G-CO.7
Understand congruence in terms of rigid motions.
Use the properties of rigid motions to show that two triangles are congruent if and only if corresponding pairs of sides and corresponding pairs
of angles are congruent.
Concepts and Skills The Standards for Mathematical Practices
Pre-requisite Connections
Determining congruence through a sequence of rigid motions (NC.M2.G-CO.6) Generally, all SMPs can be applied in every standard. The following SMPs can be
highlighted for this standard.
3 – Construct viable arguments and critique the reasoning of others
5 – Use appropriate tools strategically
7 – Look for and make use of structure
Connections Disciplinary Literacy
Use and justify criteria to determine triangle congruence (NC.M2.G-CO.8) As stated in SMP 6, the precise use of mathematical vocabulary is the expectation
in all oral and written communication
Instructional Resources
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Geometry – Congruence
NC.M2.G-CO.8
Understand congruence in terms of rigid motions.
Use congruence in terms of rigid motion.
Justify the ASA, SAS, and SSS criteria for triangle congruence. Use criteria for triangle congruence (ASA, SAS, SSS, HL) to determine whether two
triangles are congruent.
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Tasks Additional Resources
Why Does SAS Work? (Illustrative Mathematics)
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Geometry – Congruence
NC.M2.G-CO.9
Prove geometric theorems.
Prove theorems about lines and angles and use them to prove relationships in geometric figures including:
Vertical angles are congruent.
When a transversal crosses parallel lines, alternate interior angles are congruent.
When a transversal crosses parallel lines, corresponding angles are congruent.
Points are on a perpendicular bisector of a line segment if and only if they are equidistant from the endpoints of the segment.
Use congruent triangles to justify why the bisector of an angle is equidistant from the sides of the angle.
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Expose students to multiple formats for writing proofs, Example: The diagram below depicts the construction of a parallel line, above the ruler. The steps in the
such as narrative paragraphs, bulleted lists of statements, construction result in a line through the given point that is parallel to the given line. Which statement
flow diagrams, two-column format, and using diagrams below justifies why the constructed line is parallel to the given line?
without words. Students should be encouraged to focus a. When two lines are each perpendicular to a third line,
on the validity of the underlying reasoning while the lines are parallel.
exploring a variety of formats for expressing that b. When two lines are each parallel to a third line, the
reasoning. Students should not be required to master all lines are parallel.
formats, but to be able to read and analyze proofs in c. When two lines are intersected by a transversal and
different formats, choosing a format (or formats) that best alternate interior angles are congruent, the lines are
suit their learning style for writing proofs. parallel.
d. When two lines are intersected by a transversal and
corresponding angles are congruent, the lines are parallel.
Instructional Resources
Tasks Additional Resources
Points equidistant from two points in the plane (Illustrative Mathematics) Videos of Angle and Line Proofs:
Vertical angles are congruent. (Khan Academy)
Congruent angles made by parallel lines and a transverse (Illustrative Mathematics) Alternate interior angles congruent (YouTube)
Corresponding Angle Proof (YouTube)
Proving the Alternate Interior Angles Theorem (CPalms) Corresponding Angle Proofs – by contradiction (YouTube)
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Geometry – Congruence
NC.M2.G-CO.10
Prove geometric theorems.
Prove theorems about triangles and use them to prove relationships in geometric figures including:
The sum of the measures of the interior angles of a triangle is 180º.
An exterior angle of a triangle is equal to the sum of its remote interior angles.
The base angles of an isosceles triangle are congruent.
The segment joining the midpoints of two sides of a triangle is parallel to the third side and half the length.
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Draw ⃡𝐸𝐷 through point A, parallel to ⃡𝐵𝐶 . Since ⃡𝐸𝐷 and ⃡𝐵𝐶 are parallel,
alternate interior angles are congruent. Therefore, ∠𝐷𝐴𝐶 ≅ ∠𝐴𝐶𝐵 and ∠𝐸𝐴𝐵 ≅
∠𝐴𝐵𝐶. By Angle Addition Postulate, ∠𝐸𝐴𝐵 + ∠𝐵𝐴𝐶 + ∠𝐷𝐴𝐶 = ∠𝐸𝐴𝐷. Since
∠𝐸𝐴𝐷 is a straight angle, its measure is 180. Therefore 𝑚∠𝐸𝐴𝐵 + 𝑚∠𝐵𝐴𝐶 +
𝑚∠𝐷𝐴𝐶 = 180. Thus, the sum of the measures of the interior angles of a
triangle is 180.
Instructional Resources
Tasks Additional Resources
Seven Circles (Illustrative Mathematics) Exterior Angle Theorem (YouTube video)
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b. Using 𝛥𝐴𝐵𝐶 and its image 𝛥𝐴’𝐵’𝐶’, connect the corresponding pre-image and image points. Describe how
Students should understand that a dilation is a the corresponding sides are related.
transformation that moves each point along the c. Determine the length of each side of the triangle. How do the side lengths compare? How is this comparison
ray through the point emanating from a fixed related to the scale factor?
center, and multiplies distances from the center d. Determine the distance between the origin and point A and the distance between the origin and point A’. Do
by a common scale factor. the same for the other two vertices. What do you notice?
e. Determine the angle measures for each angle of 𝛥𝐴𝐵𝐶 and 𝛥𝐴’𝐵’𝐶’. What do you notice?
Students perform a dilation with a given center and scale factor on a figure in the coordinate plane.
Example: Suppose we apply a dilation by a factor of 2,
centered at the point P to the figure below.
a. In the picture, locate the images A’, B’, and C’ of the
points A, B, C under this dilation.
b. What is the relationship between ⃡𝐴𝐶 and ⃡𝐴′𝐶′?
c. What is the relationship between the length of A’B’ and
the length of AB? Justify your thinking.
Students verify that when a side passes through the center of dilation, the side and its image lie on the same line and the
remaining corresponding sides of the pre-image and images are parallel.
Instructional Resources
Tasks Additional Resources
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Geometry – Similarity, Right Triangles, and Trigonometry
NC.M2.G-SRT.2
Understand similarity in terms of similarity transformations.
Understand similarity in terms of transformations.
a. Determine whether two figures are similar by specifying a sequence of transformations that will transform one figure into the other.
b. Use the properties of dilations to show that two triangles are similar when all corresponding pairs of sides are proportional and all
corresponding pairs of angles are congruent
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Tasks Additional Resources
Similar Triangles (Illustrative Mathematics)
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Geometry – Similarity, Right Triangles, and Trigonometry
NC.M2.G-SRT.3
Understand similarity in terms of similarity transformations.
Understand similarity in terms of transformations.
Use transformations (rigid motions and dilations) to justify the AA criterion for triangle similarity.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Instructional Resources
Tasks Additional Resources
Informal Proof of AA Criterion for Similarity (EngageNY)
The AA Criterion for Two Triangles to Be Similar (EngageNY)
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Geometry – Similarity, Right Triangles, and Trigonometry
NC.M2.G-SRT.4
Prove theorems involving similarity.
Use similarity to solve problems and to prove theorems about triangles. Use theorems about triangles to prove relationships in geometric figures.
A line parallel to one side of a triangle divides the other two sides proportionally and its converse.
The Pythagorean Theorem
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among the sides of these three triangles can be
used to derive the Pythagorean relationship. Students can use triangle theorems to prove relationships in geometric figures.
Example: In the diagram, quadrilateral PQRS is a parallelogram, SQ is a
diagonal, and SQ || XY.
a. Prove that ΔXYR~ΔSQR.
b. Prove that ΔXYR~ΔQSP.
Example: Use similarity to prove the slope criteria for similar triangles.
(https://www.illustrativemathematics.org/content-standards/HSG/SRT/B/5/tasks/1876)
Instructional Resources
Tasks Additional Resources
Example proofs:
Bank Shot Task (Illustrative Mathematics)
Proof of Pythagorean Theorem using similar triangles (YouTube video)
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Geometry – Similarity, Right Triangles, and Trigonometry
NC.M2.G-SRT.6
Define trigonometric ratios and solve problems involving right triangles.
Verify experimentally that the side ratios in similar right triangles are properties of the angle measures in the triangle, due to the preservation of angle
measure in similarity. Use this discovery to develop definitions of the trigonometric ratios for acute angles.
We define the ratio of the length of the side opposite the acute angle Example: Explain why the sine of x is the same regardless of which triangle is used to find it in
to the length of the side adjacent to the acute angle as the tangent the figure below.
ratio. Note that the tangent ratio corresponds to the slope of a line
passing through the origin at an angle to the x-axis that equals the
measure of the acute angle. For example, in the diagram below,
students can see that the tangent of 45 is 1, since the slope of a line
passing through the origin at a 45 angle is 1. Using this visual, it is
also easy to see that the slope of lines making an angle less than 45
will be less than 1; therefore the tangent ratio for angles between 0
and 45 is less than 1. Similarly, the slope of lines making an angle
greater than 45 will be greater than 1; therefore, the tangent ratio for
angles between 45 and 90 will be greater than 1.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Mastering the Standard
Comprehending the Standard Assessing for Understanding
Connect with 8.EE.6 “Use similar triangles to explain why the slope
m is the same between any two distinct points on a non-vertical line
in the coordinate plane.”
We define the ratio of the length of the side opposite the acute angle
to the length of the hypotenuse as the sine ratio.
We define the ratio of the length of the side adjacent to the acute
angle to the length of the hypotenuse as the cosine ratio.
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Geometry – Similarity, Right Triangles, and Trigonometry
NC.M2.G-SRT.8
Define trigonometric ratios and solve problems involving right triangles.
Use trigonometric ratios and the Pythagorean Theorem to solve problems involving right triangles in terms of a context.
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Geometry – Similarity, Right Triangles, and Trigonometry
NC.M2.G-SRT.12
Define trigonometric ratios and solve problems involving right triangles.
Develop properties of special right triangles (45-45-90 and 30-60-90) and use them to solve problems.
30
E
B
Students begin by drawing an isosceles right triangle with leg length of x. Using the 60
Isosceles Triangle Theorem, the Triangle Angle Sum Theorem, and the Pythagorean 45
Theorem students develop and justify relationships between the sides of a 45° − 45° − C D
90°triangle.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Statistics & Probability
A statistical process is a problem-solving process consisting of four steps:
1. Formulating a statistical question that anticipates variability and can be answered by data.
2. Designing and implementing a plan that collects appropriate data.
3. Analyzing the data by graphical and/or numerical methods.
4. Interpreting the analysis in the context of the original question.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Statistics and Probability – Making Inference and Justifying Conclusion
NC.M2.S-IC.2
Understand and evaluate random processes underlying statistical experiments
Use simulation to determine whether the experimental probability generated by sample data is consistent with the theoretical probability based on
known information about the population.
This standard is extended to the idea of increasing the number of samples collected
and examining the results of more samples opposed to larger sample sizes. This
standard uses simulation to build an understanding of how taking more samples of the
same size can be used to make predictions about the population of interest.
Simulation can be used to mock real-world experiments. It is time saving and provides
a way for students to conceptually understand and explain random phenomenon.
It is suggested at this level for students to conduct simulation using tactile tools and
methods. Cards, number cubes, spinners, colored tiles and other common items are
excellent tools for performing simulation. Technology can be used to compile and
analyze the results, but should not be used to perform simulations at this level.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Statistics and Probability – Conditional Probability and the Rules for Probability
NC.M2.S-CP.1
Understand independence and conditional probability and use them to interpret data.
Describe events as subsets of the outcomes in a sample space using characteristics of the outcomes or as unions, intersections and complements of
other events.
Example: Describe the event of pulling two marbles from a bag of red/black marbles.
Example: Describe the event that the summing of two rolled number cubes is larger than 7 and even, and
contrast it with the event that the sum is larger than 7 or even.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Mastering the Standard
Comprehending the Standard Assessing for Understanding
The intersection of two For sets A and B:
sets A and B is the set of 𝐴∩𝐵 Example: If the subset of outcomes for choosing one card from a standard deck of cards is the intersection of
elements that are common two events: {queen of hearts, queen of diamonds}.
to both set A and set B. It a. Describe the sample space for the experiment.
is denoted by 𝐴 ∩ 𝐵 and is b. Describe the subset of outcomes for the union of two events.
read “A intersection B”
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Statistics and Probability – Conditional Probability and the Rules for Probability
NC.M2.S-CP.3a
Understand independence and conditional probability and use them to interpret data.
Develop and understand independence and conditional probability.
a. Use a 2-way table to develop understanding of the conditional probability of A given B (written P(A|B)) as the likelihood that A will occur
given that B has occurred. That is, P(A|B) is the fraction of event B’s outcomes that also belong to event A.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Mastering the Standard
Comprehending the Standard Assessing for Understanding
Students created two-way tables of categorical Students can use two-way tables to find conditional probabilities.
data and used them to examine patterns of Example: Each student in the Junior class was asked if they had to complete Curfew
association in MS. They also displayed chores at home and if they had a curfew. The table represents the data.
frequencies (counts) and relative frequencies Yes No Total
a. What is the probability that a student who has chores also has a curfew?
(percentages) in two-way tables. This standard
b. What is the probability that a student who has a curfew also has chores? Yes 51 24 75
Chores
uses two-way tables to establish an
understanding for conditional probability, that c. Are the two events have chores and have a curfew independent?
is given the occurrence of one event the Explain. No 30 12 42
probability of another event occurs.
Total 81 36 117
Students understand conditional probability as the probability of A occurring given B has occurred.
Example: What is the probability that the sum of two rolled number cubes is 6 given that you rolled doubles?
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Statistics and Probability – Conditional Probability and the Rules for Probability
NC.M2.S-CP.3b
Understand independence and conditional probability and use them to interpret data.
Develop and understand independence and conditional probability.
b. Understand that event A is independent from event B if the probability of event A does not change in response to the occurrence of event B.
That is P(A|B) = P(A).
Chores
Explain Yes
No 30 12 42
Total 81 36 117
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Conditional Probabilities 1 NEW
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Back to: Table of Contents
Statistics and Probability – Conditional Probability and the Rules for Probability
NC.M2.S-CP.4
Understand independence and conditional probability and use them to interpret data.
Represent data on two categorical variables by constructing a two-way frequency table of data. Interpret the two-way table as a sample space to
calculate conditional, joint and marginal probabilities. Use the table to decide if events are independent.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Mastering the Standard
Comprehending the Standard Assessing for Understanding
grade concepts to using the table to determine
independence of two events. Example: Complete the two-way frequency table at the
right and develop three conditional statements regarding
the data. Determine if there are any set of events that
independent. Justify your conclusion.
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Conditional Probabilities 1 NEW
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Statistics and Probability – Conditional Probability and the Rules for Probability
NC.M2.S-CP.5
Understand independence and conditional probability and use them to interpret data.
Recognize and explain the concepts of conditional probability and independence in everyday language and everyday situations.
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Conditional Probabilities 1 NEW
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Back to: Table of Contents
Statistics and Probability – Conditional Probability and the Rules for Probability
NC.M2.S-CP.6
Use the rules of probability to compute probabilities of compound events in a uniform probability model.
Find the conditional probability of A given B as the fraction of B’s outcomes that also belong to A, and interpret the answer in context.
𝑃(𝐴 𝑎𝑛𝑑 𝐵) Example: A teacher gave her class two quizzes. 30% of the class passed both quizzes and 60% of the class passed
So, the 𝑃(𝐴|𝐵) =
𝑃(𝐵)
the first quiz. What percent of those who passed the first quiz also passed the second quiz?
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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Conditional Probabilities 1 NEW
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Statistics and Probability – Conditional Probability and the Rules for Probability
NC.M2.S-CP.7
Use the rules of probability to compute probabilities of compound events in a uniform probability model.
Apply the Addition Rule, P(A or B) = P(A) + P(B) – P(A and B), and interpret the answer in context.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
Statistics and Probability – Conditional Probability and the Rules for Probability
NC.M2.S-CP.8
Use the rules of probability to compute probabilities of compound events in a uniform probability model.
Apply the general Multiplication Rule P (A and B) = P(A)P(B|A) = P(B)P(A|B), and interpret the answer in context. Include the case where A and
B are independent: P (A and B) = P(A) P(B).
The general rule can be explained based on the definitions of Example: Consider the same box of marbles as in the previous example. However, in this
independence and dependence. Events are either independent or case, we are going to pull out the first marble, leave it out, and then pull out another marble.
dependent. What is the probability of pulling out a red marble followed by a blue marble?
Two events are said to be independent if the occurrence of one
event does not affect the probability of the occurrence of the Example: Suppose you are going to draw two cards from a standard deck. What is
other event. the probability that the first card is an ace and the second card is a jack (just one of several
ways to get “blackjack” or 21)?
Two events are dependent if the occurrence of one event does, in
fact, affect the probability of the occurrence of the other event. Students can use the general multiplication rule to determine whether two events are independent.
The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017
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The Math Resource for Instruction for NC Math 2 Tuesday, February 7, 2017