WRM Year8 Spring Block 1 Brackets Equations Inequalities Exemplar Questions and Answers
WRM Year8 Spring Block 1 Brackets Equations Inequalities Exemplar Questions and Answers
WRM Year8 Spring Block 1 Brackets Equations Inequalities Exemplar Questions and Answers
4
3
𝑓
2𝑔
2𝑑 2𝑑
4𝑥
3 5𝑎 6𝑝
3𝑎
4𝑎
Write simplified expressions for the perimeter and area of
each shape.
4
3
𝑓
2𝑔
Perimeter 2𝑑 2𝑑
Area
Perimeter
4𝑥 Area
3 5𝑎 6𝑝
Perimeter
3𝑎
Area 4𝑎
Perimeter Perimeter
Area Area
Work out the value of these expressions when
and
𝑎𝑏 𝑎 𝑏
𝑎+𝑏 𝑏 𝑎
𝑎− 𝑏 3𝑎𝑏
2
𝑎 +𝑏
2 2
𝑎 −𝑏
2
2𝑎− 3𝑏 3𝑎
2
2
Find the value of 𝑥 when 𝑥=−2.5
Mo enters into his calculator and is surprised to get the
answer as he thinks the answer should be positive.
Discuss why the calculator shows a negative answer.
Mo is answering the question on the card.
2
Find the value of 𝑥 when 𝑥=−2.5
Mo enters into his calculator and is surprised to get the
answer as he thinks the answer should be positive.
Discuss why the calculator shows a negative answer.
The reason Mo gets a negative result is that his calculator is
following the order of operations.
In order to work out Mo should input
Solve the equations.
𝑥−1.7=−6.8
𝑥+1.7=6.8 6.8=1.7 𝑥
6.8=2 𝑥−1.7
−6.8=1.7 𝑥 𝑥
=− 6.8
1.7
1.7 𝑥−5.1=−6.8
Solve the equations.
𝑥−1.7=−6.8
𝑥+1.7=6.8 𝑥=−5.1
6.8=1.7 𝑥
𝑥=5.1 𝑥=4
6.8=2 𝑥−1.7
−6.8=1.7 𝑥 𝑥=4.25
𝑥
=− 6.8
𝑥=− 4 1.7
𝑥=−11.56
1.7 𝑥−5.1=−6.8
𝑥=−1
Simplify the expressions on the cards.
−3 𝑝+4𝑝 −8𝑝
3 𝑝+4 𝑝− 8 𝑝 −3 𝑝− 4𝑝 −8𝑝
−3 × − 4 𝑝× −2
3 ×− 4 𝑝 −3 × − 4 𝑝
−3 × 4 𝑝
Simplify the expressions on the cards.
−3 𝑝+4𝑝 −8𝑝
3 𝑝+4 𝑝− 8 𝑝 ≡− 7 𝑝 −3 𝑝− 4𝑝 −8𝑝
≡− 𝑝 ≡− 15 𝑝
−3 × − 4 𝑝× −2
3 ×− 4 𝑝 ≡− 24 𝑝 −3 × − 4 𝑝
≡− 12𝑝 ≡ 12 𝑝
−3 × 4 𝑝
≡− 12𝑝
Annie is working out and reasons she can do the same with
any number
2𝑥 5
3
Explain how these representations show that
2𝑥 5
3
3 (5 − 𝑥) −3(𝑥+5) 𝑥 (𝑥 +5)
3 (5+𝑥) 2 𝑥(5−𝑥+ 𝑦)
Expand these brackets.
3 (5+𝑥) 2 𝑥(5−𝑥+ 𝑦)
≡15 +3 𝑥 2
≡10 𝑥 − 2 𝑥 +2 𝑥𝑦
List the factors of the numbers or expressions on each card.
10 18 3𝑥
𝑥
2
2𝑥
2
6 𝑥𝑦
List the factors of the numbers or expressions on each card.
10 18 3𝑥
𝑥
2
2𝑥
2
6 𝑥𝑦
2
1,𝑥 ,𝑥
The area and the length of one of the sides is given for each
of the rectangles. Find the missing sides.
5𝑥 ?
? 6
? 4
3 𝑎+2 𝑏
The area and the length of one of the sides is given for each
of the rectangles. Find the missing sides.
5𝑥 4 𝑦
2 6
3 4
3 𝑎+2 𝑏 3 𝑎+2 𝑏
Complete the factorisations.
( ____ _____) ( ____ _____)
( ____ _____) ___
___ ____ ( ____
Complete the factorisations.
2 𝑥
( ____ _____) 𝑦
3 _____)
( ____ 2𝑥 3𝑦
𝑦
( ____ _____) 7
___ 𝑎
___ 3
____ 𝑞
( ____ 4 𝑑
5 𝑑
How many ways can you find to factorise the
expression?
Fully factorise the expression.
24 𝑥𝑦+36𝑥𝑧 𝑥( ____+_____)
( ____ _____)
How many ways can you find to factorise the
expression?
Fully factorise the expression.
3 𝑥 (8 𝑦 + 12 𝑧
6 )𝑥 ( 4 𝑦 + 6 𝑧 )
24 𝑥𝑦+36𝑥𝑧 𝑥(24
____+_____)
𝑦36 𝑧
4 𝑥𝑦
( ____ 6 𝑥𝑧
_____)
2(12 𝑥𝑦 +18 𝑥𝑧 )
Fully factorised:
Without expanding the brackets, decide whether you think
these expressions will be equivalent or not.
3 ( 𝑥+ 4 ) +2 2 𝑥+3 ( 𝑥 +4 )
2+3 ( 𝑥 + 4 ) 3 ( 𝑥+ 4 ) +2
3 ( 𝑥+ 4 ) +2 2 𝑥+3 ( 𝑥 +4 )
3 𝑥 + 145 𝑥 +12
2+3 ( 𝑥 + 4 ) 3 ( 𝑥+ 4 ) +2
3 𝑥 + 143 𝑥 + 14
Checking by building the expressions using algebra tiles.
Simplify the expressions and compare with your concrete
versions.
Ron has made mistakes in both these simplifications.
Correct answer:
Expand and simplify the expressions.
𝑥+1
Use algebra tiles to expand the expressions.
(𝑥+4)(𝑥+3) (𝑥+3)(𝑥+4)
(𝑥+4)(𝑥−3) (𝑥+3)(𝑥− 4) ( 𝑥+ 3 ) 2
Explain how the algebra tiles show that
𝑥+ 2
𝑥+1
The algebra tiles show using an area
model expansion.
(𝑥+4)(𝑥+3) (𝑥+3)(𝑥+4)
2 2
𝑥 +7 𝑥 +12 𝑥 +7 𝑥 +12
(𝑥+4)(𝑥−3) (𝑥+3)(𝑥− 4) ( 𝑥+ 3 ) 2
2 2 2
𝑥 + 𝑥 −1 2 𝑥 − 𝑥 − 12 𝑥 + 6 𝑥+ 9
Here is Tommy’s method for working out by thinking of the
calculation as
× 60 2
40 2400 80 2400+ 180+80 +6=2666
3 180 6
×
𝑎𝑏+3 𝑏 +¿
____ _____
× 60 2
40 2400 80 2400+ 180+80 +6=2666
3 180 6
×
𝑎𝑏+3 𝑏 +¿
4 𝑎+12
𝑎 _____
4____ 12
What would be different if Tommy was working out
Annie works out as
(2 𝑥+5) 2 ≡ 4 𝑥 2+ 20 𝑥+25
2 2
4 𝑥 + 20 𝑥 +25 ≠ 4 𝑥 +25
2 2
(2 𝑥+5) ≡ 4 𝑥 + 20 𝑥+25
4 𝑥2 + 20 𝑥 +25 ≠ 4 𝑥2 +25
Solve the equations
Solve the equations
𝑎=11 𝑏=1
𝑥=−1.2 𝑥 =9
𝑒= 2
Compare these solutions of the equation
Explain the steps in each method.
Which approach do you prefer?
Compare these solutions of the equation
Explain the steps in each method.
Which approach do you prefer?
𝑥 × 4 +7 20
𝑦 +7 × 4 20
Write and solve equations to find the values of and
𝑥 × 4 +7 20
or
𝑦 +7 × 4 20
The area of the rectangle is 72 cm2
Work out the value of and hence find the perimeter of the
rectangle.
3 (2
𝑥+ cm
5)
The area of the rectangle is 72 cm2
Work out the value of and hence find the perimeter of the
rectangle.
3 (2
𝑥+ cm
5)
Perimeter cm
Which of the inequalities does the number satisfy?
___
___
___ ___
Mo says “If , then ”
Explain why Mo is right. is one greater than
Complete the spider diagram.
___14
___ 32
5
___ 𝑥>10 20
___
___ 32 ___ 17
If , which of the cards are true and which are false?
10< 𝑥
40< 4 𝑥
− 𝑥 >−10
If , which of the cards are true and which are false?
10< 𝑥 True
40< 4 𝑥 True
− 𝑥 >−10 False
Solve the inequalities.
𝑥+ 2>−7 𝑥+ 2<−7
𝑥+ 2<7 𝑥 −2 ≤ 7 𝑥 −2 ≥ −7
2 𝑥+2< 7 4 𝑥+2≥ −7 3+ 5 𝑥 ≤7
Solve the inequalities.
𝑥+ 2<7 𝑥 −2 ≤ 7 𝑥 −2 ≥ −7
𝑥< 5 𝑥≤9 𝑥 ≥ −5
2 𝑥+2< 7 4 𝑥+2≥ −7 3+ 5 𝑥 ≤7
𝑥< 2.5 𝑥 ≥ −2.25 𝑥 ≤ 0.8
Write an inequality and solve it to find the possible range of
values for Whitney’s number.
What is the smallest integer Whitney could be thinking of?
𝑥
This triangle had sides + 4
and 11 cm. 𝑥
Work out the range of
possible values of .
cm
Each square represents and each cube represents
Write expressions for each card. The first one is done for you.
𝑥
This triangle had sides + 4
and 11 cm. 𝑥
Work out the range of
possible values of .
cm
cm
Write down the equation shown by the bar model.
4 𝑥+12=2 𝑥+18
Write down the new equation if the two leftmost s are
removed from the bars. Work out the value of .
Use the bar model to help you complete the workings to find
the value of .
5 𝑦 =3 𝑦 +15
−𝟑 𝒚 −𝟑 𝒚
etc.
Use the bar model to help you complete the workings to find
the value of .
5 𝑦 =3 𝑦 +15
−𝟑 𝒚 −𝟑 𝒚
÷𝟐 ÷𝟐
𝑦 =7.5
Solve the equations.
Total area
Dora and Amir are both given the same starting number.
Greatest value
What’s the same and what’s different about the cards?
𝐶=𝜋 𝑑 𝑃=2𝑙+2𝑤 1
𝐴= 𝑏h
2
𝐷
𝑆=
𝑃=4 𝑠 𝑇 𝐴=𝑙𝑤
Investigate how the value of the subject of the formula
changes as the other variables change.
Which of these formulas do you recognise?
Circumference of Perimeter of a Area of a
a circle rectangle triangle
𝐶=𝜋 𝑑 𝑃=2𝑙+2𝑤 1
𝐴= 𝑏h
2
Perimeter of a Speed
Area of a
square rectangle
𝐷
𝑆=
𝑃=4 𝑠 𝑇 𝐴=𝑙𝑤
Explain the meaning of all the variables in the formulas.
Discuss as a class
Investigate how the value of the subject of the formula
changes as the other variables change.
Discuss as a class
An equation is anything with
an equals sign.
Rosie
Explain why Rosie is wrong.
Which of these cards show equations? What do the other
cards show?