UML: which circumstances such that a rectangle is not a polygon?

Question

I hope the question is clear?

Thanks in advance!

Answer 1

Did you mean to ask in which case a Rectangle is not a regular polygon? In that case it wouldn't be regular, if it's not a square.

In a regular polygon all sides are equal and all angles are equal

A non-square rectangle only has equal angles, so it wouldn't be one. Not sure what this has to do with UML though...