In the triangle below x 10 Use the Law of Cosines to solve

In the triangle below, x = 10. Use the Law of Cosines to solve the triangle. A = degree B = degree C = degree

Solution

x^2 = 12^2 +18^2 - 2*12*18cosA

10^2 = 12^2 +18^2 - 2*12*18cosA

cosA = 0.852

A = 31.57 deg

18^2 = 12^2 +10^2 - 2*12*10cosB

cosB = -0.416

B = 114.62 deg

C = 180 -A - B = 33.805 deg