Question

3.
If the exterior angle of an isosceles triangle is 110° and its interior opposite
angles are equal, then each angle is equal to
a) 50
b) 55
c) 45
d) 60°​

Answer 1

Each angle is equal to 60

Answer 2

Given:

The exterior angle of an isosceles triangle is 110° and its interior opposite

angles are equal

To find:

The value of each angle is equal to

Solution:

The exterior angle of an isosceles triangle is 110°

The interior angle of this exterior angle is,

180° - 110° = 70°

Let the other 2 angles be "x" as they are equal.

Thus, we have,

x + x + 70° = 180°

2x = 110°

x = 55°

Therefore, the each angle is equal to 55°

Option (b) 55° is correct.