How many degrees in an isosceles triangle?

In an isosceles triangle, we have two sides called the legs and a third side called the base. The angle located opposite the base is called the vertex. The vertex angle B of isosceles triangle ABC is 120 degrees. Find the degree measure of each base angle. read more

Since the angles of a triangle add up to 180 degrees, the third angle is 180 minus two times a base angle, making the formula for the measure of an isosceles triangle's apex angle: A = 180 - 2b. Where A is the apex measure and b is the measure of one base angle. read more