Answer:
D. 16
Explanation:
1. Because these are vertical angles (opposite pair of angles that are formed by intersecting lines), these are congruent. That means (8x-8) = (7x+8).
2. (Solving)
Step 1: Subtract 7x from both sides.
Step 2: Add 8 to both sides.
Step 3: Check if solution is correct.
Therefore, the answer is D. 16.