# Triangular Pyramid

*Go to Surface Area or Volume.*

Triangular Pyramid Facts

**Notice these interesting things:**

- It has 4 Faces
- The 3 Side Faces are Triangles
- The Base is also a Triangle
- It has 4 Vertices (corner points)
- It has 6 Edges
- It is also a Tetrahedron

## Surface Area

When side faces are the same:

**Surface Area** = [Base Area] + \frac{1}{2} × Perimeter × [Slant Length]

### Example: Base Area is 28, Perimeter is 20, Slant length is 5

Surface Area | = [Base Area] + \frac{1}{2} × Perimeter × [Slant Length] | |

= 28 + \frac{1}{2} × 20 × 5 | ||

= 28 + 50 | ||

= 78 |

When side faces are different we can calculate the area of the base and each triangular face separately and then add them up.

## Volume

**Volume** = \frac{1}{3} × [Base Area] × Height

### Example: base area is 28, height is 4.5

Volume | = \frac{1}{3} × [Base Area] × Height | |

= \frac{1}{3} × 28 × 4.5 | ||

= \frac{1}{3} × 126 | ||

= 42 |