In Exercise, rewrite each expression without absolute value bars.TVs keep getting fancier...

In Exercise, rewrite each expression without absolute value bars.

TVs keep getting fancier and bigger, but prices do not. The bar graph at the top of the next column shows the average price of a TV in the United States from 2007 through 2012.

Source: Consumer Electronics Association

Here are two mathematical models for the data shown by the graph. In each formula, P represents the average price of a TV x years after 2007.

a. Which model better describes the data for 2007?

b. Does the polynomial model of degree 2 underestimate or overestimate the average TV price for 2012? By how much?