graphing equation, algebra homework help

You want to celebrate all of your recent successes.  You decide to reward yourself and a special someone with a vacation to a destination of your choosing.  For your trip you will need to stay in a hotel/resort and rent a car.

You decide to rent a car for the duration of your trip.  You have two options.  Write an equation for each company that depicts the total cost of the rental, y, based on the number of days, x.

Cheepers Rent-A-Car:

$39/day with a one-time charge of $20 for insurance/fees

Busters:

$49/day but all additional fees are included in the price of the rental

Be sure to label each equation with the company it corresponds to.