SOLUTION: A triangle has sides of 11 ft, 12 ft, and 15 ft. What is of the angle opposite the shortest side?

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Question 927223: A triangle has sides of 11 ft, 12 ft, and 15 ft. What is of the angle opposite the shortest side?
Found 2 solutions by Alan3354, Fombitz:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
A triangle has sides of 11 ft, 12 ft, and 15 ft. What is of the angle opposite the shortest side?
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Use the Cosine Law.

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Use the law of cosines,
cos%28A%29=%2812%5E2%2B15%5E2-11%5E2%29%2F%282%2812%29%2815%29%29
cos%28A%29=%28144%2B225-121%29%2F%28360%29
cos%28A%29=%28248%29%2F%28360%29
cos%28A%29=31%2F45
Time for a calculator.