A classroom has an area of (30x^3+8x^2) ft^2, with a width of 2x feet. What is the length of the floor?

P.S: I know the answer, but I don't know how to solve for it.

3 answers

since width = area/length, you have
(30x^3 + 8x^2) / (2x) = 30x^3/2x + 8x^2/2x = 15x^2 + 4x
L w = 30 x^3 + 8 x^2
but w = 2 x
so
L = (30 x^3 + 8 x^2) / 2 x
= 15 x^2 + 4 x
Thank you!!