Exercise 7 Page 534

Let's start by finding x. We see that 58 and 2x form a linear pair. Therefore, by the Linear Pair Postulate, we know that these angles are supplementary. This means they add up to 180. 2x+ 58=180 Let's solve this equation.

To find the measure of y, we use the fact that 2y and 58 are corresponding angles. Since the lines that are cut by the transversal are parallel, by the Corresponding Angles Theorem, we know they are congruent. 2y=58 ⇔ y=29