Find x. assume that any segment that appears to be tangent is tangent.
a. 10
b. 5
c. 12
d. 15

D. x=15° is the correct answer, hope this helps.

Step-by-step explanation:

The measurement of the outer angle is the semi-difference of the arcs it encompasses.

see the attached figure to better understand the problem

∠x=(1/2)[arc AB-arc CD]

arc AB=40°

Remember that the diameter divide the circle into two equal parts

arc CD=180°-(130+40)°=10°

substitute

∠x=(1/2)[40°-10°]=15°