SOLUTION: Find angle B of the given triangle: A = 120o, b = 42.3 in, c = 136.4 in Round your answer to two decimal places.

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Question 1120726: Find angle B of the given triangle:
A = 120o, b = 42.3 in, c = 136.4 in
Round your answer to two decimal places.
Answer by josgarithmetic(39625) About Me  (Show Source):
You can put this solution on YOUR website!
b%5E2%2Bc%5E2-2bc%2Acos%28120%29=a%5E2

a%5E2=%2842.3%29%5E2%2B%28136.4%29%5E2-2%2842.3%29%28136.4%29%2Acos%28120%29

a%5E2=%2842.3%29%5E2%2B%28136.4%29%5E2-2%2842.3%29%28136.4%29%2A%28-1%2F2%29

a%5E2=%2842.3%29%5E2%2B%28136.4%29%5E2%2B%2842.3%29%28136.4%29

a=161.752805--------length of side opposite point A.

Now use Law Of Sines to find measure of angle at point B.