Question

A bathtub is draining at a constant rate. After 2 minutes, it holds 30 gallons of water. 3 minutes later, it holds 12 gallons of water. Write an equation that represents the number y of gallons of water in the tub after x minutes

Answer 1

y = -18 x + 66.

Since the bathtub is draining at a constant rate, it can be modeled with equation y = mx + c ( m is the constant draining rate )

To find m, do 12 - 30 = 18