# Why can't a triangle have a right angle and an obtuse angle?

##### 1 Answer

Dec 24, 2015

It would violate the theorem of the sum of the interior angles of a triangle summing up to

#### Explanation:

We know that sum of all interior angles of a triangle is

If we assume that one angle is right angle of

Sum of the 2 angles is then

It cannot be possible due to equation (1). (Contradiction).

Therefore our initial assumption of