Question

In a anglePQR,PQ=PR.If angleP=70diegree, what are measures of angleQ and angleR

Answer 1

PQ = PR

This means that the triangle is isosceles.

angle P = 70°

THEOREM : angles opposite to equal sides of a triangle are equal.

∴  ∠ Q = ∠ R

let  ∠Q = ∠ R = x

70 + x + x = 180°

70 + 2x = 180°

2x = 180 - 70 =  110°

x = 110 ÷ 2 = 55°

∴ ∠Q = ∠R = 55°