Answer:
∠ BNM = 150°
Step-by-step explanation:
Project MN to meet AB at point P, then
Δ ANP is a right triangle with sum of angles = 180°, thus
x = 180° - (90 + 30)° = 180° - 120° = 60°
∠ BNM = x + 90 = 60 + 90 = 150°
