Theory:
A 'prism' is a solid figure with a uniform cross section. Here are some examples of prisms:
| Rectangular based prism:
| Circular based prism: (Cylinder)
| Triangular based prism:
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The surface area of any prism equals the sum of the areas of its faces, which include the floor, roof and walls. Because the floor and the roof of a prism have the same shape, the surface area can always be found as follows:
From now on we will call the 'floor' the 'base'. The height of the prism = 'H'.
The surface area of a prism = 2 × area of base + perimeter of base × H
The actual formula used to find the surface area will depend on the shape of the base of the prism.
For example:
| Rectangular based prism Base shape: Rectangle, length 'L' and width 'W' Area of base: L × W Perimeter of base: 2(L+W) Surface area = 2LW + 2(L+W)H |  |
| Circular based prism Base shape: Circle, radius 'R' Area of base: pR² Perimeter of base: 2pR Surface area = 2pR² + 2pRH
|  |
| Triangular based prism Base shape: Triangle: base 'b', height 'h', and sides S1, S2 and S3 Area of base: ½b×h Perimeter of base: S1+ S2 + S3 Surface area = bh + (S1+ S2 + S3)H
|  |
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