Image source: http://www.insulshield.net/carpet.gif
The cost of an item that is affected by its area, such as the cost for carpeting,
is often based on a polynomial with degree 2 because area is measured in 2 dimensions.
If the price of carpeting is $18 per square foot, then the cost, c, to
carpet a square room with side s (in feet) can be determined by the equation
c = 18s2.