To find the surface area of a rectangular prism, you use the formula:

SA=2lw+2lh+2whSA=2lw+2lh+2whSA=2lw+2lh+2wh

where:

• lll = length,
• www = width,
• hhh = height.

This formula calculates the area of all six rectangular faces of the prism by adding the areas of the three pairs of identical faces (length × width, length × height, and width × height) and doubling each because each pair has two faces

. Steps to calculate surface area:

1. Measure or identify the length, width, and height of the rectangular prism.
2. Calculate the area of each pair of faces:
   • lwlwlw for the top and bottom,
   • lhlhlh for the front and back,
   • whwhwh for the two sides.
3. Multiply each area by 2 (since there are two of each face).
4. Add all these values together to get the total surface area.

Example: If a rectangular prism has length 5 cm5,cm5cm, width 3 cm3,cm3cm, and height 4 cm4,cm4cm, then:

SA=2(5×3)+2(5×4)+2(3×4)=2(15)+2(20)+2(12)=30+40+24=94 cm2SA=2(5\times 3)+2(5\times 4)+2(3\times 4)=2(15)+2(20)+2(12)=30+40+24=94,cm^2SA=2(5×3)+2(5×4)+2(3×4)=2(15)+2(20)+2(12)=30+40+24=94cm2

So, the surface area is 94 square centimeters

. This method ensures you account for all six faces of the prism to find the total surface area accurately