The resale value of a sports car declines as the number of miles driven increases. Data from a website that values used cars show that a car with 25,000 miles had a value of $32,200. A similarly equipped car with 50,000 miles was valued at $31,000. (See Example 3 in this section.)
Find a linear function for the value of the car y (in dollars) in terms of the number of miles driven, x.
y =


Use the function to approximate the value of a car (in dollars) that has been driven 45,000 miles.