Finding Lateral Area

The lateral area is the surface area of a 3D figure, but excluding the area of any bases. Lateral Area is often abbreviated L.A. Imagine a soup can. Now cut down the side of the can and roll it flat. What was the circumference of the base is now the length of a rectangle. To find the area of this rectangle which is the same as the lateral area, multiply this length by the width, which was the height of the can.
Lateral Area of a prism: perimeter × height
Lateral Area of a cylinder: circumference × height.
Lateral Area of a regular pyramid: ½ perimeter × slant height.
Lateral Area of a right cone: ½ perimeter × slant height.

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