SOLUTION: what are the angles of a triangle that has sides of 21 28 and 30

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Question 265374: what are the angles of a triangle that has sides of 21 28 and 30
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Use the law of cosines:
c^2 = a^2 + b^2 - 2abcos(C)
900 = 441 + 784 - 2*21*28*cos(C)
cos(C) =~ 0.27636
C =~ 73.96º
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Do the other 2 the same way, or use the Law of Sines