geometry
posted by scott .
Can anyone help me to solve this, please?
A right prism has a polygonal base with n sides. Each side has a length of 5 in. The altitude of the prism is 20 in.
If the base had n+1 sides, each still having a side of length 5 in, by how much, in square inches, would the lateral area of the prism increase by? Express your answer as a number only.
I would be mighty grateful! Thanks...sz

Al = Ph = 5n * 20 = 100n in^2. = Lateral Area.
Al = Ph = (5(n+1)) * 20 = (5n+5)*20 =
(100n + 100) in^2.
Amt. Increased=(100n+100) 100n = 100 in^2.