all square and all rectangles are equiangular?

Yes.

thank you

You're welcome.

To determine if all squares and all rectangles are equiangular, we need to understand the definitions of both shapes.

A square is a four-sided polygon with all sides of equal length and all angles measuring 90 degrees. Since all angles in a square are 90 degrees, it is equiangular.

On the other hand, a rectangle is also a four-sided polygon, but it does not require all sides to be of equal length like a square. However, a rectangle has opposite sides that are parallel and internal angles that measure 90 degrees. So, all the angles in a rectangle are also 90 degrees, making it equiangular as well.

Therefore, both squares and rectangles have equal angles, and hence, both shapes are equiangular.