Question

In a Δ ABC, if AB = AC and ∠B = 70°, find ∠A.

Comments

https://www.sarthaks.com/111171/in-a-abc-if-ab-ac-and-b-70-find-a

Answer 1

Given: 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°

Answer 2

As AB=AC (given)

Then angle B = angle C =70°

From property of triangle:

A+B+C =180°

A+70°+70°=180°

A= 40°

Answer 3

 

 ABC is equal to AC and angle b is equal to 70 degree then in triangle abc are the mysterious ab is equal to AC and angle b is equal to angle c 70 level 2 angle c in triangle abc

Angle a +Angle b + angle c is equal to 180 degree due to property of triangle

Angle + 70 + 70 equal to 180

Angle a + 140 equal to 180

Angle a is equal to 40 degree