# Pyramid (Geometry)

See how to find the surface area/volume of a pyramid.

3 examples and their solutions.

## Pyramid

### Definition

that has a vertex, a polygon base,

and triangle lateral faces.

## Regular Pyramid

### Definition

whose base is a regular polygon

and whose lateral faces are

all congruent isosceles triangles.

So the vertex and the center of the base

are the endpoints of the height.

## Regular Pyramid: Surface Area

### Formula

A = B + 12Ph

_{s}

= (base area) + (lateral area)

h

_{s}: slant height

### Example

Surface area?

Solution ↓

↓

B = 10

^{2}- [1]

= 100

P = 4⋅10 - [2]

= 40

h

_{s}= 13

A = 100 + 12⋅40⋅13

= 100 + 20⋅13

= 100 + 260

= 360

[1]

[2]

Perimeter of the base: square

Close

## Pyramid: Volume

### Formula

V = 13Bh

### Example

### Example

Volume?

Solution