Geometrical shape of the prism is that of a triangular prism with a triangular base and rectangular sides. Prisms are named for their base, so a prism with a pentagonal base is called a pentagonal prism and prism with a triangular base is called a triangular prism. In the prism the line segments are required to be parallel to any fixed line that intersect both planes. Surface area of the prism is the sum of lateral surface area and twice the base area of the prism.

## Surface Area of a Prism Formula

The area of the surfaces of the prism is called its surface area of the prism. Surface area of the prism is the sum of lateral surface area and twice the base area of the prism. Square units are used to measure the surface area of the prism.

Formula:

Surface Area of a Prism = L + 2B

Where,
L = Lateral surface area of the prism
B = Base area of the prism.

## How to find the Surface Area of a Prism

A prism is a solid figure with a uniform cross section. The surface area of any prism equals the sum of the areas of its faces, which include the top, bottom and sides of the prism. Because the top and the bottom of a prism have the same shape. The actual formula used to find the surface area will depend on the shape of the base of the prism.

The surface area of a prism = Lateral surface area + 2 × area of base

Steps for finding the Surface Area of a Prism:

Step 1:
Find the lateral surface area of the prism.

Step 2:
Find the area of the base of the prism.

Step 3:
Multiply the result of step 2 with 2.

Step 4:
Add the results of step 1 and step 2.

Step 5:
Write answer in the proper square unit of measurement.

Example:
What is the surface area of a prism whose ends have an area of 15 in2 and its lateral area is 12 in2.

Solution:
Step 1:

Area of one end of prism = 15 in2
Lateral surface area of the prism = 12 in2

Step 2:

The surface area of a prism = Lateral surface area + 2 × area of base

=> SA = 12 + 2 x 15

= 12 + 30

= 42

Hence the surface area of the prism is 42 in2 .