By magic, my previous posting evaporated !
1. irregular, regular [various constructions]
2. star 5/2 maths
3. Holly star

Maths Polygon Area_Perimeter.sm (33,38 KiB) descargado 1321 vez(es).
Maths Polygon Star 5_2.sm (965,24 KiB) descargado 1377 vez(es).