Question

The height of an equilateral rectangular prism decreases by two units. The new lateral area is less than the original by how much?

Answer 1

the volume of a rectangular prism is length x width x height

if the height will be decreased by 2 units

new volume = l x w x (h-2)

new volume = lwh - 2lw

lw is the area of a rectangle

therefore it's less than by twice the area of its base

Answer 2

Oh! I get it now. I thought it was less than twice the perimeter of the base before.

Thanks!

Answer 3

<tips imaginary hat>