Answer:
180˚ or C
Explanation:
Complementary angles are two angles that add up to 90˚.
Since m∠A = 40˚ then we can write and equation where ∠B equals x.
40 + x = 90
40 - 40 + x = 90 - 40
x= 50
m∠B = 50˚
Supplementary angles are two angles that add up to 180˚.
Since ∠B is the supplement of ∠C, we will use x as the value of ∠C.
50 + x = 180
50 - 50 + x= 180 - 50
x= 130
So ∠C = 180˚
Thus, 50˚ + 130˚ = 180˚