The answer is 8/17.
Cosine, or cos, is the adjacent line/ the hypotenuse
In this case, the hypotenuse is 17 since it is the longest side in this right triangle. The adjacent line is 8 since it is adjacent, or touching, to the Angle A. 15 is the tangent that is facing opposite from Angle A.
If we plug in the given numbers correctly, the answer should be 8/17.
