Question

If the degree measure of an angle is 40° less than 3 times the degree measure of its supplementary angle, what is the degree measure of the angle?
A.
50°
B.
55°
C.
125°
D.
130°

Answer 1

b

Answer 2

125

Answer 3

Write an equation, then solve it.

Let x be the measure of the supplement.

3 times the supplement is 3x
40 deg less than 3 times the supplement is 3x - 40

The angle measures 3x - 40 and the supplement measures x.

The measures of supplementary angles add up to 180, so

3x - 40 + x = 180

Solve this equation for x. This is the measure of the supplement.

Then plug in the value of x into 3x - 40 to find the measure of the angle.