Question

9. In a triangleABC, AB=AC and angle B=70°. What is
the measure of angle C?​

Answer 1

In a Δ ABC, AB = AC and ∠B = 70° ∠B = ∠C [Angles opposite to equal sides are equal] Therefore, ∠B = ∠C = 70° Sum of angles in a triangle = 180° ∠A + ∠B + ∠C = 180° ∠A + 70° + 70° = 180° ∠A = 180° – 140° ∠A = 40°