Volume and Surface Area of Prisms
Rule

Surface Area of a Cube

Consider a cube with a side length
Cube with the side length s

The surface area of the cube is given by the following formula.

Proof

The surface area of a prism is the sum of the lateral area and the combined areas of the two identical bases.
Since the base of a cube is a square with a side length its area is equal to the square of
The perimeter of the square base can be calculated as the product of and
Finally, the height of the cube is also equal to the side length
Now these values will be substituted into the formula and the resulting equation simplified.
Exercises