SOLUTION: If the ratio of three sides of a triangle is a:b:c =7:8:9 then show that cos A:cosB:cosC= 14:11:6

SOLUTION: If the ratio of three sides of a triangle is a:b:c =7:8:9 then show that cos A:cosB:cosC= 14:11:6

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Question 835833: If the ratio of three sides of a triangle is a:b:c =7:8:9 then show that cos A:cosB:cosC= 14:11:6
Answer by richard1234(7193) (Show Source): You can put this solution on YOUR website!
Assume that the side lengths of the triangle are a = 7, b = 8, c = 9. Apply law of cosines three times on each of the angles, and you're done.
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