Question

Right triangle PQR is shown, where m angle Q is not equal to m angle R. Which expression is equivalent to sin(Q)? A. sin(R). B. sin(P). C. cos(R). D. cos(P).

Answer 1

C. cos(R).

Reason: In a right triangle the two acute angles Q and R are complementary (Q + R = 90°), so sin(Q) = cos(90° − Q) = cos(R).