It has 6 vertices.
6
It is a triangular prism that has 5 faces, 6 vertices and 9 edges
v=60-20
Edges join two vertices. Three or more edges meet at a vertex (it could be two if not in a polyhedron).
A polyhedron has 30 edges and 12 vertices. How many faces does it have
It has 6 vertices.
A sphere is not a polyhedron because it has no edges, no vertices and no flat faces The word 'polyhedron' means many faces.
eight
6
It is a triangular prism that has 5 faces, 6 vertices and 9 edges
A polyhedron must have at least 4 faces, at least 4 vertices and at least 6 edges.
This polyhedron has 7 vertices and 12 edges.
12 vertices A prism with an n-sided base will have 2n vertices, n + 2 faces, and 3n edges.
Such a polyhedron cannot exist. According to the Euler characteristics, V + F - E = 2, where V = vertices, F = faces, E = edges. This would require that the polyhedron had only two faces.
v=60-20
Edges join two vertices. Three or more edges meet at a vertex (it could be two if not in a polyhedron).