SOLUTION: In triangle ABC, a=8, b=9, and cosC= 2/3. Find c.

Question 1105984: In triangle ABC, a=8, b=9, and cosC= 2/3. Find c.
Answer by ikleyn(52842) (Show Source): You can put this solution on YOUR website!
.
Cosine law:

c^2 = a^2 + b^2 - 2ab*cos(C) = 8^2 + 9^2 - .


Complete these calculations on your own.

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On cosine law, see the lessons
- Proof of the Law of Cosines revisited
- Solve triangles using Law of Cosines
in this site.

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