Percentage by which the average value of mid sized car decreases each year = 8% Retail value of a car today = v dollars Amount of decrease in the value of the car after 1 year = (8/100) * v = 2v/25 dollars Then The equation that represents the value of the car after 1 year = v - (2v/25) dollars = (25v - 2v)/25 dollars = 23v/25 dollars So following this expression the value of the mid sized car can be easily determined after 1 year. I hope this is the answer you were looking for and the procedure is also clear to you.
try using a vertical line, if you move the vertical line across the graph and the line touches the graph only at one point, than it means it is a function
