SOLUTION: Given the Triangle ABC with b=8,c=10, A=74 degrees what is the length of a?

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Question 199242: Given the Triangle ABC with b=8,c=10, A=74 degrees what is the length of a?
Answer by HyperBrain(694) About Me  (Show Source):
You can put this solution on YOUR website!
We use cosine law to solve this problem.
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a%5E2=b%5E2+%2B+c%5E2+-2bc%2Acos+A
=8%5E2+%2B+10%5E2+-2%2A8%2A10%2Acos+74
=64%2B100-160cos+74
=120
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So, a=sqrt%28120%29=10.9