Is it possible to bake a cake that can be divided by one straight cut into 4 pieces?
A square piece of paper is cut into 6 pieces, each of which is a convex polygon. 5 of the pieces are lost, leaving only one piece in the form of a regular octagon (see the drawing). Is it possible to reconstruct the original square using just this information?
Cut a square into three pieces, from which you can construct a triangle with three acute angles and three different sides.