How do you find the value of x to find the measurement of the angle?

(2x - 10)0(x + 20)0

In this lesson you will learn how to find the measurements of angles created when parallel lines are cut by a transversal

by using alternate interior angles and alternate exterior

angles.

Let’s ReviewLet’s Review

Vertical Angles

43

21

6587

t

p

q

Adjacent Angles

Corresponding Angles

Let’s ReviewA Common Mistaket

p

q

1 24

5 67 8

3Interior Angles

Exterior Angles

Exterior Angles

Let’s ReviewCore Lessont

p

q

1 24

5 67 8

3

Alternate Interior Angles

Let’s ReviewCore Lesson

(2x - 10)0(x + 20)0

2x - 10 = x + 20

x - 10 = 20

x = 30

(30 + 20)0

500

(2(30) - 10)0

500

Let’s ReviewCore Lessont

p

q

1 24

5 67 8

3

Alternate Exterior Angles

Let’s ReviewCore Lesson

(4y + 30)0

(7y + 6)0

t

p

q

7y + 6 = 4y + 303y + 6 = 30

y = 83y = 24

7(8) + 6 56 + 6 620

4(8) + 30 32 + 6 620

In this lesson you have learned how to find the measurements of angles created when parallel lines are cut by a transversal

by using alternate interior angles and alternate exterior

angles.

Let’s ReviewGuided Practice

Find the value of x. (x-10)0

1040

t

p

q

Let’s ReviewExtension Activities Name all the alternate exterior angle pairs.

12

2

1

34 5

8 7

11

10

6

9Name all the alternate interior angle pairs.

Let’s ReviewExtension Activities

Find the measure of angles 1, 7 and 53

t

p

q

2

51010

67

1

8

Let’s ReviewExtension Activities

Find x and y.

(8y - 15)0

t

p

qx0

(y2) 0

Let’s ReviewQuick Quiz

Find the value of x and the measurement of each angle.

(12x + 7)0

t

p

q

(5x + 21) 0

Let’s ReviewQuick Quiz Find the value of x and the

measurement of each angle.

(3x + 15)0(5x - 5)0