Exercise 7 Page 108

The measure of the angle formed by the intersection of lines a and t is about 120^(∘). Let's do the same for line b.

The measure of the angle formed by the intersection of lines b and t is about 115^(∘).

Extra

Types of Angle Pairs

Let's review what we know about different types of angle pairs. We will use the graph below as an example.

Now we can list the different types of angle pairs together with their definitions.

Pairs of Angles
Type	Definition	Example
Supplementary Angles	Together, they form a straight line and their measures add up to 180^(∘).	∠ 1 and ∠ 3
Vertical Angles	They lie on the opposite sides of the point of intersection of two lines.	∠ 1 and ∠ 4
Corresponding Angles	They lie in corresponding positions on the same side of the transversal.	∠ 3 and ∠ 7
Alternate Interior Angles	They lie between the two lines on opposite sides of the transversal.	∠ 4 and ∠ 5
Alternate Exterior Angles	They lie outside the two lines on opposite sides of the transversal.	∠ 2 and ∠ 7