x y xy xxy xyy xxyy x10y 90-90x 90-90y 60-9010xy 90-9010x10y 90-90x10y 90-90x20y 90-90x30y 90-90x40y 90-90x50y 90-90x60y xypi2 xypi2r xypi2y 90xypi2 0-180xypi2 360xypi2 90-90-0-180xy xsiny xsinysin xsinycos xsinytan xcosycos 180xsinycos 360xsinycos tetrahedron octahedron cube icosahedron dodecahedron