Answer:
82.8
Step-by-step explanation:
LAW OF COSINES
b^2 = a^2 + c^2 − 2ac cos(b) formula
12^2 = 10^2 + 8^2 - 2(10)(8) cos (b) substitute and calculate
144 = 100 + 64 - 160 cos (b) add like terms
144 = 164-160 cos (b) subtract 164
- 20 = -160 cos (b) divide by -160/reduce
1/8 = cos (b) inverse cos each side
b = 82.8
