Answer = 23 degrees
Explanation
1. Since vertical angles are congruent you can set the equations equal to one another like x+15 = 5x-17.
2. Subtract x on both sides to combine like terms . That gives 15 = 4x - 17
3. Add 17 on both sides to combine like terms. That gives 4x = 32.
4. Divide 4 on both sides to solve for x. That results in x = 8.
5. To find the measure of b, you can input 8 into A since A=B and it’s quicker math. So 8 + 15 = 23 degrees