How many faces, edges and vertices of a triangular prism

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A triangular prism is a three-dimensional solid with specific properties related to its faces, edges, and vertices.

1. Faces

A triangular prism has:

  • 2 triangular faces (the top and bottom).
  • 3 rectangular faces (the sides connecting the triangles).

So, the total number of faces is: \[ 2 \text{ (triangular)} + 3 \text{ (rectangular)} = 5 \text{ faces} \]

2. Edges

To count the edges, consider:

  • Each triangular face has 3 edges. Since there are 2 triangular faces, this contributes \(2 \times 3 = 6\).
  • Additionally, there are 3 edges connecting corresponding vertices of the two triangular faces (one edge for each vertex of the triangle).

So, the total number of edges is: \[ 6 \text{ (from the triangles)} + 3 \text{ (connecting edges)} = 9 \text{ edges} \]

3. Vertices

A triangular prism has:

  • Each triangular face has 3 vertices, and since there are 2 triangular faces, this contributes \(2 \times 3 = 6\) vertices.

So, the total number of vertices is: \[ 6 \text{ vertices} \]

Summary

Putting it all together, for a triangular prism:

  • Faces: 5
  • Edges: 9
  • Vertices: 6

This can also be confirmed using Euler's formula for polyhedra, which states: \[ V - E + F = 2 \] where \(V\) is the number of vertices, \(E\) is the number of edges, and \(F\) is the number of faces.

Substituting our values: \[ 6 - 9 + 5 = 2 \] Thus, Euler's formula holds true, confirming our counts are correct.

Final Count

  • Faces: 5
  • Edges: 9
  • Vertices: 6