To find the lateral area of a prism, you can use the formula:
Lateral Area = perimeter of the base x height
Perimeter of the base = 2(length + width)
Perimeter of the base = 2(4 + 5) = 18
Lateral Area = 18 x 21 = 378 sq in
To find the total surface area of a prism (including the lateral area and the two bases), you can use the formula:
Surface Area = 2(base area) + lateral area
Base area = length x width = 4 x 5 = 20
Surface Area = 2(20) + 378 = 40 + 378 = 418 sq in
Therefore, the lateral area of the prism is 378 sq in and the total surface area is 418 sq in.
Use formulas to find the lateral area and surface area of the prism.
4in
5in
21in
1 answer
1 answer