Answer:
[tex]y=20x[/tex]
We know that the slope is 20 in this situation, as we can tell that 20 gallons are used every time the dishwasher is ran, therefore, everytime y increases by 1, x will increase by 20. Since the problem starts at the origin (0, 0), there is no y-intercept, so we don't have to worry about that.
