The measure of an inscribed angle is half the measure of an intercepted arc. So 1/2 mCE = m∠CDE
158 ÷ 2 = 79
You need to find x so you're going to set your equation of (8x - 9) = 79
Then you're going to add 9 to both sides to get 8x = 88
Divide both sides by 8 to get x = 11
Part 2:
We know that WY is 180 because it's a semicircle. Using this and the knowledge that ∠WXY is half the measure of the intercepted arc (180), we know that our equation should be (13x - 1) = 90
add 1 to both sides and our equation is (13x = 91)
