Answer:
83 degrees
Explanation:
17^2 = 8^2 + 16^2 - 2 * 8 * 16 * cos (X)
289 = 64 + 256 - 16 * 16 * cos(X)
289 = 320 - 256 cos(X)
289-320 = -256 cos(X)
- 31 = -256 cos(X)
31 = 256 cos(X)
31/256 = 256/256 cos(X)
0.121094 = cos (X)
x = arccos 0.121094
x = 83.04475538