Question

EXERCISE 5A
1. In a triangle ABC, if AB = AC and angleA= 70°, find angleB and angleC.​

Answer 1

Answer:

Angle B = Angle C = 55°

Step-by-step explanation:

lf AC = AB,

Then Angle B = Angle C ---- (1)

Angle A + Angle B + Angle C = 180° ------ (2)

(Angle sum property)

From eq. (1) & (2)

70° + Angle B + Angle C = 180°

Angle B + Angle C = 110°

From eq (1)

Angle B + Angle B = 110°

2 Angle B = 110°

Angle B = 55°

Angle B = Angle C = 55°