Question

Can a polyhedron have 10faces,20edges,and 15vertices

Answer 1

No, a polyhedron cant have 10 faces , 20 edges, and 15 vertices as Euler formula is not satisfied 

Euler's  formula = faces+ vertices-edges = 2 

                                10 + 15-20 = 2

                                  25-20  = 2

                                         5≠2

So it cant have  10 faces , 20 edges, and 15 vertices