SOLUTION: Given triable ABC with b=21 feet, c=13 feet and a=17 feet. find the measure of angle A

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Question 880153: Given triable ABC with b=21 feet, c=13 feet and a=17 feet. find the measure of angle A
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
Angle A is between the sides b and c. Angle A would be understood opposite positionally from side a.

b%5E2%2Bc%5E2-2ac%2Acos%28A%29=a%5E2 symbolically for your particular example.
(Law of Cosines)