How to Find the Surface Area of a Right Rectangular Prism

To find the surface area of a right rectangular prism, you need to know the dimensions of the prism: length (l), width (w), and height (h).

The formula for the surface area (SA) of a right rectangular prism is:

SA = 2(lw + lh + wh)

Here’s how it works:

  • Identify the dimensions: First, measure the length, width, and height of the prism.
  • Calculate each face area: The prism has three pairs of faces. Calculate the area of each pair:
    • lw: area of the top and bottom faces
    • lh: area of the front and back faces
    • wh: area of the left and right faces
  • Sum the areas: Add up all three areas to find the total area of one pair. Then, multiply by 2 to account for both pairs of each face.

For example, if a rectangular prism has a length of 3 units, a width of 4 units, and a height of 5 units, you would calculate:

SA = 2((3 * 4) + (3 * 5) + (4 * 5))

This simplifies to:

SA = 2(12 + 15 + 20) = 2(47) = 94 square units

And that gives you the total surface area of the prism!

More Related Questions