# PP2 Dissections

### Author : Gavin Theobald

For PP2 dissections the strips must be overlaid so that the area of overlap is
only half that of the shapes. This means that only half the shapes are yet
dissected so that it is necessary to overlay the strips a second time.

So to dissect a hexagon to a rectangle we first obtain strips for these two
polygons:

These strips are now overlaid twice. Note that when overlaying the second strip
it can only be positioned in one of two ways, the second position being obtained
by rotating the strip 180 degrees.

This gives the following dissection:

Here is a second example of a PP2 dissection. One piece is shaded to make it
clear that it is a single piece.

Finally, if PP2 dissections are possible, why not PP3 or even PP4 and above?