In ΔABC, the measure of ∠C=90°, CB = 35, AC = 12, and BA = 37. What ratio represents the cosine of ∠A?

Cosine is adjacent over hypotenuse.

C is the right angle so AB is the hypotenuse.

A is the angle we're interested in, so AC is the adjacent.

cos A = AC/AB = 12/37

Answer: 12/37