SOLUTION: Please help! If side a = 10, side b = 7, and side c = 8, find angle A. Thank you, Tami

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Question 149987: Please help!
If side a = 10, side b = 7, and side c = 8, find angle A.
Thank you, Tami

Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
If side a = 10, side b = 7, and side c = 8, find angle A.
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Use the Law of Cosines:
2bc*Cos(A) = b^2 + c^2 - a^2
Cos(A) = [49 + 64 - 100] / 2*7*8 = 0.11607...
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A = cos^-1(0.11607...) = 83.33.. degrees
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Cheers,
Stan H.

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