SOLUTION: If you are given 3 sides of a triangle, explain how you would find all three angles?

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Question 1091279: If you are given 3 sides of a triangle, explain how you would find all three angles?
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
KNOWN sides a, b, c;
Unknown angle measure opposite of each of those sides, A, B, C;

Find any angle, for example, at point C:
a%5E2%2Bb%5E2-2ab%2Acos%28C%29=c%5E2------Law Of Cosines
-
a%5E2%2Bb%5E2-c%5E2=2ab%2Acos%28C%29
cos%28C%29=%28a%5E2%2Bb%5E2-c%5E2%29%2F%282ab%29-----and then inverse cosine to find angle at C.

More than one way, to continue.

Answer by MathTherapy(10553) About Me  (Show Source):
You can put this solution on YOUR website!

If you are given 3 sides of a triangle, explain how you would find all three angles? 
With sides being a, b, and c, use Law of Cosines, as follows: