Answer:
d. 15, 30, 135
Step-by-step explanation:
A triangle's interior angles on a flat surface add up to 180 degrees.
a. 90 * 3 = 270 != 180
b.(80 * 2) + 200 = 360 != 180
c.40 + 50 + 60 = 160 != 180
d.15 + 30 + 135 = 45 + 135 = 180, so it has to be d.
