Write an equation in the form y mx b for the average gas mileage y miles per gallon of a car driven at a speed of x mph miles per hour Use the data points 0 65 and 90 20 to find the equation Then use the equation to predict the gas mileage when the car is driven at 50 mph y x 65 gas mileage at 50 mph is 40 miles per gallon Oy 2x 65 gas mileage at 50 mph is 40 miles per gallon Oy x 65 gas mileage at 50 mph is 40 miles per gallon Oy x 65 gas mileage at 50 mph is 45 miles per gallor