Chapter 11.1, Problem 5GP

To determine

To find the measure of the angle $\angle 8$ in the given figure.

Answer to Problem 5GP

  $\angle 8={128}^{\circ }$

Explanation of Solution

Given:

  

Here, $r\left|\right|s$ and $w$ is a transversal. $\angle 1={128}^{\circ }$ .

Calculation:

The angle $\angle 1$ and $\angle 5$ are corresponding angles. So, these two angles are equal.

Therefore, $\angle 5={128}^{\circ }$ .

Now, observe that $\angle 5$ and $\angle 8$ are opposite angles. So, they must be equal.

Therefore, $\angle 8={128}^{\circ }$ .

Conclusion:

The measure of angle $\angle 8$ is ${128}^{\circ }$ .