Q:

Find the measure of angleC in the following triangle

Accepted Solution

A:
Answer:C = 58.88 degreesStep-by-step explanation:We can use the law of cosines to find the missing angle measurementc^2 = a^2 +b^2 -2ab cosCRearranging and solving for cos C2ab Cos C = a^2 +b^2 - c^2Divide by 2abcos(C) =  a^2 + b^2 − c^2              ------------------------                          2abSubstituting what we know  a = 31 b = 21   c = 27                             31^2 + 21^2 - 27^2      cos C        =  -----------------------------                              2(31)(21)       cos C = .516897081Take the inverse cos on each sidecos^-1 cos C = cos ^-1 (.516897081)C = 58.88 degrees