Suppose you start with a full tank of gas (20 gallons) in your truck. After driving 6 hours, you now have 10 gallons left.

If x is the number of hours you have been driving, then y is the number of gallons left in the tank.

At what rate is your truck using gas? State your answer as a reduced fraction.

gallons per hour ?

Find an equation of a line in the form y = mx + b that describes the amount of gas in your tank.

y =