Since the rate of change is constant, the data in the table can be modeled by a linear equation with a slope of -2.5. Using one of the points, let's say ( 8, 155), we can write a linear model in Point-Slope Form.
y- 155= -2.5(x- 8)
In this model, x is time in minutes and y is the amount of water in the tank in gallons. Since we are asked to express the amount of water as a function of time, we need to solve this equation for y.
