I built a storage shed in the shape of a rectangular box on a square base. The material that I used for the base cost $4 per square foot, the material for the roof cost $2 per square foot, and the material for the sides costs $2.50 per square foot; and I spent $450 altogether on material for the shed.
Express the volume of the shed as a function of the (length of each) side of the square base.
