Question

What is the measure of the vertex angle of an isosceles triangle if one of its base angles measures 65° and its congruent sides each measure 15 cm?

Answer 1

Since base angles of an isosceles triangle are congruent the other base angle is also 65. since the three angles together sum to 180 thst leaves 180-65-65=180-130 = 50 degrees for the vertex angle