Algebra Word Problems
posted by mike .
when going more than 38 miles per hour the gas mileage of a certain car fits the model y=43.81  3.95x where x is the speed of the car in miles per hor and y is the miles per gallon of gas. Based on model what speed will the car average 15 miles per gallon

15=43.813.95x
subtrace 43.81 from each side, then divide both sides by 3.95