Question

Angle A measures 4x + 40 degrees and angle B measures x – 10
degrees. If angles A and B are complementary, what is the
measure of angle B?

Answer 1

Answer:

2°

Step-by-step explanation:

Since, angles A and B are complementary.

Therefore,

$m\angle A + m\angle B = 90\degree \\\\

(4x +40)\degree + (x-10)\degree = 90\degree \\\\

(4x+x +40-10)\degree = 90\degree \\\\

(5x +30)\degree = 90\degree \\\\

5x + 30= 90\\\\

5x = 90 - 30\\\\

5x = 60\\\\

x = \frac{60}{5}\\\\

x = 12\\\\

m\angle B = (x-10)\degree \\\\

m\angle B = (112-10)\degree \\\\

m\angle B = 2\degree$