Question

Solve for C.

15
50°
20
c
15
Law of Cosines: c^2 = a^2+ b^2 - 2ab•cosC

c = [?]
Round your final answer to the nearest tenth.

Answer 1

`\textit{Law of Cosines}\\\\ c^2 = a^2+b^2-(2ab)\cos(C)\implies c = √(a^2+b^2-(2ab)\cos(C)) \\\\[-0.35em] ~\dotfill\\\\ c = √(15^2+20^2~-~2(15)(20)\cos(50^o)) \implies c = √( 625 - 600 \cos(50^o) ) \\\\\\ c \approx √( 625 - (385.6726) ) \implies c \approx √( 239.3274 ) \implies c \approx 15.5`

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