Question

I know that the formula for finding the surface area of a rectangular prism is 2ab + 2bc + 2ac , but how do I "fill in the variables", with knowing the correct numbers to solve the problem?

Answer 1

You're right but just to simplify your life, make the formula this...

A=2(wl+hl+hw)

w=width

h=height

l=length

Easy, just fill in the "variables."

Example,

l=2

w=2

h=2

Plug it in..

2(2*2+2*2+2*2)

2(4+4+4)

2(12)

24

Thus, your surface area example...

Easy.