Question

A family’s well pumps on average 8 gallons of water per min. The well’s tank had 1200 gal of water in the morning. Which equation models the amount of water in the tank y after it has been pumping for x min?

y = 8x – 1200



y = –8x + 1200



y = 8x + 1200



y = –8x – 1200

Answer 1

Situation 1:

If water is pumped from the tank for use by the family, then the equation is:

y = -8x + 1200

Situation 2:

If the water is pumped from the water source in the tank to be stored in the tank, then the equation is:

y = 8x + 1200