Question

Note: Figure is not drawn to scale.

If m1 = 26° and m2 = 11°, what is m3?
A. 154°
B. 143°
C. 169°
D. 128°

Answer 1

$Sum\ of\ angles\ in\ triangle\ is \ equal \ to\ 180^{\circ}\\\\ m1+m2+m3=180\\\\ 26+11+m3=180\\\\ 37+m3=180\ \ \ | subtract\ 37\\\ m3=143\\\\ Answer\ is \ B$