Question

If m DFC = 40° and m
d = 55°, then mBG=

Answer 1

The measure of arc BG is 25°

Answer 2

The measure of arc BG is 25°

Explanation:

we know that

The measure of the inner angle is the semi-sum of the arcs comprising it and its opposite.

so

m∠DFC=(1/2)[arc CD+arc BG]

we have

m∠DFC=40°

arc CD=55°

substitute and solve for arc BG

40°=(1/2)[55°+arc BG]

80°=[55°+arc BG]

arc BG=80°-55°=25°