How to solve basic trigonometry?

Assuming angle N = 90°

a) ∠m = 48°

b) n = 20.18

c) k = 13.5

Step-by-step explanation:

a) ∠m = 180° - 90° - 42° = 48°  because the sum of all three interior angles of a triangle equals 180°

b) cos 42 = 15/n

0.7431 = 15/n

n = 20.18

c) tan 42 = k/15

0.9004 = k/15

k = 13.5

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