SOLUTION: Given triangle ABC with a=12,b=10 and c=8 find the angles in degrees and minutes.

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Question 252654: Given triangle ABC with a=12,b=10 and c=8 find the angles in degrees and minutes.
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
Given triangle ABC with a=12,b=10 and c=8 find the angles in degrees and minutes

cos%28A%29+=+%28b%5E2%2Bc%5E2-a%5E2%29%2F%282bc%29

cos%28A%29+=+%2810%5E2%2B8%5E2-12%5E2%29%2F%282%2A10%2A8%29

cos%28A%29+=+%28100%2B64-144%29%2F%28160%29

cos%28A%29+=+20%2F160=1%2F8=0.125

A+=+%2282.81924422%B0%22+=+%2282%B049%27%22 

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cos%28B%29+=+%28a%5E2%2Bc%5E2-b%5E2%29%2F%282ac%29

cos%28B%29+=+%2812%5E2%2B8%5E2-10%5E2%29%2F%282%2A12%2A8%29

cos%28B%29+=+%28144%2B64-100%29%2F%28192%29

cos%28B%29+=+108%2F192=9%2F16=0.5625

B+=+%2255.77113367%B0%22+=+%2255%B046%27%22

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cos%28C%29+=+%28a%5E2%2Bb%5E2-c%5E2%29%2F%282ab%29

cos%28C%29+=+%2812%5E2%2B10%5E2-8%5E2%29%2F%282%2A12%2A10%29

cos%28C%29+=+%28144%2B100-64%29%2F240

cos%28C%29+=+180%2F240=3%2F4=.75

C+=+%2241.40962211%B0%22+=+%2241%B025%27%22

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Checking:

 82° 49'
 55° 46'
 41° 25'
--------
178°120' = 180°

Edwin