Using the 48° angle, we find out that the angle opposite of angle y° is also 48° according to the corresponding angles theorem. Then, you would subtract 48 from 180 to get the degrees of angle y, which would be 132°. Next, you need to subtract 132 from 180 to get the angle measure of the (5x - 17)° angle. (180 - 132 = 48) Once you have done that, all you have to do now is figure out what value of x makes it equal to the degree measure you found by subtracting 132 from 180. I tried it with x = 13, which came out as a correct answer. So x must be 13.