Question

If a side of a triangle is extended, then the measure of the exterior angle so formed is equal to the sum of the measures of ____________ angles.

• A. one adjacent and one non-adjacent interior
  
• B. two non-adjacent interior
• C. any two interior
  
• D. two right
  

Answer 1

The correct option is B two non-adjacent interior

If a side of a triangle is extended, then the measure of the exterior angle so formed is equal to the sum of the measures of two non-adjacent interior angles.
Example:


In the given triangle, when the side $AC$ is extended to point $B$, the measure of the exterior angle $\angle DCB$ so formed is equal to the sum of the measures of the two non-adjacent interior angles $\angle DAC$ and $\angle ADC.$

$\to$ Option B is correct.