Simply cutting a corner off a square can lead to a puzzling
activity.

So the little triangle is removed:

This little triangle is then put back making sure that a corner of
the triangle is always touching a corner of the shape that the
triangle came from, and two edges line up.
We can then make new shapes:

Which were made as follows:

So here's the challenge: Can you make all the following and tell us
about how they are made from the two shapes?