To find the measure of angle 1 we have to apply the circle theorem.
The correct formula to find the measure of angle 1 is One-half(a° – b°).
Given:
Find the measure of angle 1.
<h3>What is the circle theorem?</h3>
As per the circle theorem, the angle of the vertex of a circle is equal to half of the difference of the intercepted arc.
The angle at the vertex is angle 1.
The intercepted angle is the angle a and angle b.
Thus, the correct formula to find the measure of angle 1 is One-half(a° – b°).
Learn more about circle theorem here:
brainly.com/question/12960962