Solution:
Consider the Given Isosceles Triangle
Considering the Possibilities
Case 1. When two equal angles are of 70°
Let the third angle be x.
Keeping in mind , that sum of Interior angles of Triangle is 180°.
70° + 70° + x= 180°
140° +x= 180°
x= 180°- 140°
x= 40°
Case 2:
When an angle measures 70°, and two equal angles measure x°.
Keeping the same property of triangle in mind, that is sum of interior angles of triangle is 180°.
70° + x° + x° = 180°
⇒ 70° + 2 x° = 180°
⇒ 2 x° = 180° - 70°
⇒ 2 x° = 110°
Dividing both sides by 2, we get
x= 55°
