Tessellation of an Equilateral Pentagon

#### Tessellating Equilateral Pentagon

This is a simple tessellating pattern: an equilateral pentagon, four of which make a hexagon. Of course, it is not a regular pentagon. But it has interesting properties. Within each pentagon, there are two right angles, the measure of the other three angles are to be calculated.

I first figured out the measure of one of the two congruent angles, which is 45° + arccos(sqrt(2)/4). Then, I mirrored the sketches around. This makes a nice starting des