SOLUTION: In triangle ABC, a = 4, b = 3, and cos C = -1/2. What is the length of c?

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Question 957415: In triangle ABC, a = 4, b = 3, and cos C = -1/2. What is the length of c?
Answer by stanbon(75887) About Me  (Show Source):
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In triangle ABC, a = 4, b = 3, and cos C = -1/2. What is the length of c?
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c^2 = a^2+b^2-2ab*cos(C)
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c^2 = 16 + 9 - 2*4*3(-1/2)
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c^2 = 25-12
c = sqrt(13)
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Cheers,
Stan H.
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