# math

posted by .

How do i find the lateral area and the surface area of a rectangular prism

with the height of 8.5"
the width 4"
the depth 3.25"
I don't want you to do it for me i want to know what formula or how i start to solve for those two things please

• math -

http://library.thinkquest.org/20991/geo/solids.html

• math -

ok i found how to do the surface area but i still don't know what to use for the lateral area

• math -

i don't get lateral area either

• math -

This is from the above site:

"The lateral area L (area of the vertical sides only) of any right prism is equal to the perimeter of the base times the height of the prism (L = Ph)."

If the perimeter of the base is 10 inches and the height is 3 inches, then the lateral area is 30 inches.

• math -

the lateral area of a solid is the surface area with the base excluded.

So if it says to find the surface area of a cone you would include the circle, but if you are to find the lateral area of a cone you would find only the top part surface.