A rental car company offers a rental package for a mid-size car.

​The cost is comprised of a fixed
$
40
$40 administrative fee for the cleaning and maintenance of the car plus a rental cost of
$
45
$45 per day.

​

​Using

x for the number of days and

y for the total cost in dollars, construct a linear function to model the relationship between the number of days and the total cost of renting a mid-size car.