SOLUTION: Find the angles in the triangle when a = 13, b = 12, and c = 11. Round your answers to the nearest tenth. Im not sure how to find angles our of the sides or what ever this is imply

Algebra ->  Trigonometry-basics -> SOLUTION: Find the angles in the triangle when a = 13, b = 12, and c = 11. Round your answers to the nearest tenth. Im not sure how to find angles our of the sides or what ever this is imply      Log On


   

Question 882802: Find the angles in the triangle when a = 13, b = 12, and c = 11. Round your answers to the nearest tenth. Im not sure how to find angles our of the sides or what ever this is implying im so lostt.
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find the angles in the triangle when a = 13, b = 12, and c = 11. Round your answers to the nearest tenth.
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Use the Cosine Law
c%5E2+=+a%5E2+%2B+b%5E2+-+2ab%2Acos%28C%29 Angle C is opposite side c
11%5E2+=+13%5E2+%2B+12%5E2+-+2%2A13%2A12%2Acos%28C%29
cos(C) = 192/312 = 8/13
C =~ 52.02 degs
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You can get another angle the same way, or use the Law of Sines
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c/cos(C) = b/cos(B) = a/cos(A)
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After you find a 2nd angle, the 3rd is 180 - sum of the other 2.