Question

An octagonal pyramid ... how many faces does it have, how many vertices and how many edges? A triangular prism ... how many faces does it have, how many vertices and how many edges? a triangular pyramid ... how many faces does it have, how many vertices and how many edges?

Answer 1

Explanation:

Octagonal pyramid has 8 sloping faces and the base.

Total 9 faces.

Also 8 slope edges and 8 base edges

Total 16 edges.

It has 1 + 8

Total 9 vertices.

A Triangular prism has 5 faces and 9 edges.

Also 6 vertices.

Triangular pyramid has 4 faces, 4 vertices and 6 edges.

Note: The relation betseem faces, vertices and sdges in a polyhedron is given by Euler's formula:

T + V - E = 2

So we see, for an octagonal pyramid:

9 + 9 - 16 = 2.

Answer 2

1: 8 faces and 9 with the base 9 vertices and 16 edges

2: 3 faces and 5 with the bases 6 vertices and 9 edges

3: 3 faces and 4 with the base 4 vertices and 6 edges