Answer:
8/17
Explanation:
From the triangle, given sin C=15/17 we will use the trigonometry identity to get the ratio of cosC. Using the SOH CAH TOA identity;
sinC = opp/hyp = 15/17
opposite = 15
hypotenuse = 17
According to pythagoras theorem;
hyp² = opp²+adj²
17² = 15² + adj²
adj²= 17²-15²
adj = √64
adj = 8
Since cosC = adj/hyp
cosC = 8/17
The ratio of cos is 8/17