SOLUTION: A triangle has 3 measurements from A,B,C. Length AB=18, BC=13 and CA=16. What's the angle in between the measurements 16 and 18. (18 is the hypotenuse, 13 is the opposite side and
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Question 681180: A triangle has 3 measurements from A,B,C. Length AB=18, BC=13 and CA=16. What's the angle in between the measurements 16 and 18. (18 is the hypotenuse, 13 is the opposite side and 16 is the adjacent side.) USE SINE LAW Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! A triangle has 3 measurements from A,B,C. Length AB=18, BC=13 and CA=16. What's the angle in between the measurements 16 and 18.
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Law of Cosines:
a^2 = b^2 + c^2 - 2bc*cos(A)
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cos(A) = [b^2 + c^2 -a^2]/(2bc)
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Notice the b and c are the sides that make angle A
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Your Problem:
cos(A) = [16*2+18^2-13^2]/(2*16*18) = 0.7135
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A = cos^-1(0.7135) = 39.08 degrees
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Cheers,
Stan H.
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