Help on 15 and 16 its geometry!!

Step-by-step explanation:

15. If A and B are complementary angles, then sin A = cos B and cos A = sin B.

So if sin A = m, then cos B = m.

16. If sin A = cos B, or cos A = sin B, and A and B are acute, then A and B are complementary.

a. cos 60° = sin θ

60° + θ = 90°

θ = 30°

b. sin 71° = cos θ

71° + θ = 90°

θ = 19°

c. sin θ = cos (θ + 20°)

θ + θ + 20° = 90°

2θ = 70°

θ = 35°

d. sin (θ − 60°) = cos θ

θ + θ − 60° = 90°

2θ = 150°

θ = 75°

$450 is the answer.

step-by-step explanation:

30% of 450 = 135

450-135=315