Decagram

The decagram, or dag, is a star polygon with 10 sides. A regular decagram has equal sides and equal angles.

Vertex coordinates
Coordinates for a decagon of unit edge length, centered at the origin are all sign changes of:


 * (±1/2, ±$\sqrt{(5-√5)/2}$/2)
 * (±(3-$\sqrt{5}$)/4, ±$\sqrt{(5-2√5))}$)
 * (±($\sqrt{(5-2√5)}$)-1/2, 0)