SOLUTION: A triangle has side lengths of 27,17 and 22. What is the measure of angle A formed by the two shorter sides?

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Question 1071980: A triangle has side lengths of 27,17 and 22. What is the measure of angle A formed by the two shorter sides?
Answer by Edwin McCravy(20081) About Me  (Show Source):
You can put this solution on YOUR website!

Use the law of cosines in this form:

cos%28ANGLE%29%22%22=%22%22

The two shorter sides, 17 and 22, are the adjacent sides,
and the longest side, 27, is the opposite side.  So A is
the largest angle:

cos%28A%29%22%22=%22%22+%2817%5E2%2B22%5E2-27%5E2%29%2F%282%2A17%2A22%29

cos%28A%29%22%22=%22%22+%28289%2B484-729%29%2F748

cos%28A%29%22%22=%22%22+44%2F748

cos%28A%29%22%22=%22%22+1%2F17

A%22%22=%22%22%2286.62771332%B0%22

Round off as you were told.

Edwin