LP Parallel Lines Feb 2018
LP Parallel Lines Feb 2018
LP Parallel Lines Feb 2018
I. Objective
At the end of the lesson, the students are expected to:
1. Define parallel line and perpendicular line
2. Determine the conditions under which lines and segments are parallel or perpendicular
III. Procedure
1. Activity
Daily Routine
Drill/ Recall
Motivation
Let ask the students How to describe the parallel line and perpendicular line?
2. Analysis
Development of the Lesson
Parallel and Perpendicular Lines
This lesson explains what are parallel and perpendicular lines and has varied exercises for the students. The
lesson also includes a video where I show how to draw a perpendicular line and a rectangle using a protractor
or a triangular ruler.
2. Which line segments in these figures are parallel? Which are perpendicular?
a. Line segments AB and BC
are ____________________________________.
are ____________________________________.
are ____________________________________.
are ____________________________________.
In the video below, I show you how to a right angle (or a perpendicular line to a given line) using either a protractor or a triangular ruler. I
also show how to draw a line perpendicular to a given line through a point on the line, or through a point not on the line. Lastly, I draw a
rectangle with given side lengths, using a protractor to make right angles, and a regular ruler to measure the sides.
First, draw a point on the given line. Next you will need a protractor or a triangular ruler.
1) Using a protractor:
Align the dot and the straight side of your protractor. Draw the line.
Also align your existing line and the 90° mark on the protractor.
Align the inside edge with the given line. Draw the line.
Align the dot with the outside edge.
4. Draw a line that is perpendicular to the given line and goes through the given point.
5. Complete these drawings so you get: a) a rectangle; b) a square. Use a protractor or a triangular
ruler to make sure the lines you draw are perpendicular to the existing lines.
a. b.
6. a. Draw here any triangle that has a right angle. It is called a right triangle.
(Hint: Start by drawing two lines that are perpendicular.)
Method 2: A protractor.
10. Find rays, lines, and line segments that are either parallel or perpendicular to each other. You can use
these shorthand notations: ∥ for parallel and ⊥ for perpendicular.
For example, l ∥ m means l is parallel to m, and AB ⊥ CD means AB is perpendicular to CD.
b.
3. Abstraction
How do you determine the conditions under the line and segments are parallel or perpendicular?
4. Application
Evaluation
IV. Agreement
Study about parallel lines and perpendicular lines.
Prepared by:
February 9, 2017
I.Objective
At the end of the lesson, the students are expected to:
1. Define parallel line and perpendicular line
2. Determine the conditions under which lines and segments are parallel or perpendicular
III.Procedure
1.Activity
Daily Routine
Drill/ Recall
Motivation
Let ask the students How to describe the parallel line and perpendicular line?
2.Analysis
* Development of the Lesson
Parallel and Perpendicular Lines
Now that we have a better understanding of lines and angles, we are ready to begin applying some of these
concepts onto the Caresian coordinate plane. We will use our previous knowledge of slopes
and algebraic equations to learn about parallel and perpendicular lines in the coordinate plane.
Although the coordinate plane is used extensively in the study of algebra, it is very useful in geometry as
well. In algebra, when you study slope, essentially what you are dealing with is angles. More specifically,
the slope of a line is the measure of an angle of a line from a perfectly horizontal line (or the x-axis).
This concept is illustrated below.This goes to show that different areas of mathematics are connected
and consistent with each other.
Parallel Lines
Recall that two
lines in a
plane that
never intersect are called parallel lines. Working with parallel lines in the coordinate plane is fairly
straightforward. The reason for this is because the slope of a line is essentially the measure of an angle of a line
from a perfectly horizontal line (or the x-axis). Thus, in the coordinate plane, if we want two different lines to
never intersect, we simply apply the same slopes to them.Let's take a look at the following equations:
How do we determine if these lines are parallel or if they intersect at some point?
First, it will help to put both equations in slope-intercept form. The first equation is already of this form so we do
not need to change it. The second equation, however, needs to be manipulated. Let's work it out:
Now, we add y to both sides of the equation to get
4. Application
Evaluation
IV.Agreement
Study about the parallel line and perpendicular line for your Test tomorrow.
Prepared by:
III. Procedure
1. Activity
Daily Routine
Checking of Attendance
Motivation
2. Analysis
Development of the Lesson
Parallel lines – are straight lines which lie on the same plane and do not intersect.
The symbol for parallel lines is ||
A line is a Transversal if and only if it intersects two or more lines, each at a different point.
3. Abstraction
Recall the definition of parallel line and transversal line
4. Application
Evaluation
Answer Activity 7 on page 454
I. Study the figure and answer the following questions as accurate as you can. The
figure below shows a || b with t as transversal.
Name:
1. 2 pairs of corresponding angles __________ _________
2. 2 pairs of alternate interior angles __________ _________
3. 2 pairs of alternate exterior angles __________ _________
4. 2 pairs of interior angles on the same __________ _________ side of the transversal
5. 2 pairs of exterior angles on the same __________ _________ side of the transversal
II. Based on your observations of the measures of the angles formed by parallel lines
cut by a transversal, what can you say about the following angles?
a. Corresponding angles ________
b. Alternate interior angles ________
c. Alternate exterior angles ________
d. Pairs of exterior angles ________
e. Interior angles on the same side of the transversal ________
Prepared by: