Given that the measure of the base angle of an isosceles triangle is one-fourth that of its vertex angle, determine the measure of the apex angle.
An isosceles triangle has 2 base angles that are equal in measure.
Write an equation to show that the sum of the triangle's angle
measures is . Let represent the measure of the
vertex angle and represent the measure of each base
angle. Solve for .
So, the vertex angle has a measure of .