Q:

Angle ABC is formed by two tangents intersecting outside of a circle. If minor arc AC = 110°, what is the measure of angle ABC?

Accepted Solution

A:
If two tangents intersect at a point outsides the circle, then its angle measure is equal to one-half the difference of its intercepted arcs.

A circle has 360 degrees, so to find the measure of the major arc, subtract 110 from 360 to get 250.

ABC = 1/2(250 - 110)
ABC = 1/2(140)
ABC = 70

The measure of angle ABC is 70 degrees.

Hope this helps =)