Question

in an isosceles triangle the vertex angle is 110° . find the exterior angle adjacent to either of the base angle​

Answer 1

Let x be the exterior angle (in degrees).

Then the exterior angle is equal to the sum of the two non-adjacent interior angles.

x+45=180 (sum of adjacent angles forming a straight line)

x=180−45=135 degree ⇒ exterior angle.

Interior angle: sum of the angles inside =180

The 2 base angles of an isosceles triangle are equal, so we'll represent each as z.

z+z+45=180

2z=180−45

2z=135

z=67.5 degree ⇒ interior angle.

So, interior angle =67.5 degree, exterior angle =135 degree.