Pentadecagon

A pentadecagon or quindecagon or 15-gon is a shape with 15 sides and 15 corners.

 Regular pentadecagon 
All sides of a regular pentadecagon are the same length. Each corner is 156°. All corners added together equal 2340°.

 Area 
The amount of space a regular pentadecagon takes up is

a is the length of one of its sides.

 Uses 
160pxA regular triangle, decagon, and pentadecagon can completely fill a plane vertex.

15