Question #N108
In the figure below, triangle ABC is isosceles with AB = AC, and the measure of angle BAC is 40 degrees. What is the measure of angle ABC?
A. 40
B. 70
C. 80
D. 100
Correct Answer is: B
Since triangle ABC is isosceles, angle ABC and angle ACB have the same measure. The sum of the measures of the angles in a triangle is 180 degrees. Therefore, the measure of angle ABC is (180 - 40)/2 = 70 degrees.