mark a right angle in right triangle(Powerpoint)?

[ptspace]

I'm trying to sketch a right triangle with a right angle mark. Is there any
simple way to do this. I'm trying connectors, but unsuccessfully.

 

[Reb]

Have you tried using Basic Shapes?

 

[Sandy]

I think the arc shape in the Drawing Menu under Basic shapes should help.

 

[John Wilson]

Combination of basic shapes Right angle triangle and small rectangle maybe?