A watering can dispenses water at a rate of 0.35 gallon per minute. The original volume of water in the can was 9 gallons. Which set of ordered pairs shows the volume of water in the can in gallons (y) as a function of time in minutes (x) from the first minute after the can starts dispensing water?

{(1, 9.0), (2, 8.65), (3, 8.30)}
{(9.0, 1), (8.65, 2), (8.30, 3)}
{(8.65, 1), (8.30, 2), (7.95, 3)}
{(1, 8.65), (2, 8.30), (3, 7.95)}

Question

A watering can dispenses water at a rate of 0.35 gallon per minute. The original volume of water in the can was 9 gallons. Which set of ordered pairs shows the volume of water in the can in gallons (y) as a function of time in minutes (x) from the first minute after the can starts dispensing water?

 {(1, 9.0), (2, 8.65), (3, 8.30)}
 {(9.0, 1), (8.65, 2), (8.30, 3)}
 {(8.65, 1), (8.30, 2), (7.95, 3)}
 {(1, 8.65), (2, 8.30), (3, 7.95)}

mathmale · Answer

I'd suggest you write a formula that will predict the REMAINING volume of water in the can after x minutes.  Hint:  Your formula must have a non-zero y-intercept and a negative slope.  Find that intercept and the slope.  Your equation?