Law of Cosines: A triangular field has sides of lengths 18, 37, 43 yd. Enter your answer as a number; answer should be accurate to 2 decimal places. Find the largest angle in degrees:

Answer 1

The lafgest angle, θ, is opposite the largest side.

Using the Law of Cosines, 43² = 18² + 37² - 2(18)(37)cosθ

cosθ = (43² - 18² - 37²) / (-2(18)(37))

cosθ = -0.117117117

θ = Cos^-1(-0.117117117) = 96.7°