7. A contractor that builds houses uses the following expression to estimate bids for his customers, based on
the square footage of the house. For roofing materials he estimates 98x + 1000. For concrete and dirt
work he estimates 350x + 3000. For flooring materials he estimates 300x + 1200. For walls, insulation, and
windows he estimates 900x + 1500. For electrical, plumbing, and HVAC work he estimates 120x + 6500. If
a customer chose to have the contractor provide all of these, write a polynomial that he could use to give
his customers an estimate.