dodecohedron

Hi, mr Rutten I want to draw a dodecohedron. I want to overlap the edge of the pentagon what is the simpliest way of doing that without using expression? I can do that roughly with the number slider but I can't know the exact overlapping points or vectors. Is there any way to make the number slider do that? 

if we had seen snap points or there were geometric constraints like in autocad parametric , This would be possible.