To determine the correct graph for the scenario where a bathtub is filled with 40 gallons of water and drains at a rate of 8 gallons per minute, we will model the relationship between time in minutes and the amount of water remaining in the tub.
- The bathtub starts with 40 gallons.
- It drains at a constant rate of 8 gallons per minute.
The equation that represents the amount of water (W) left in the tub after t minutes is:
\[ W(t) = 40 - 8t \]
This is a linear equation where:
- The y-intercept (at t = 0) is 40 gallons.
- The slope (rate of change) is -8 gallons per minute, indicating that the water decreases by 8 gallons for every minute that passes.
To find when the tub will be empty, we set W(t) = 0: \[ 40 - 8t = 0 \] \[ 8t = 40 \] \[ t = 5 \]
Thus, the tub will be empty after 5 minutes.
Considering the options:
- Option A shows a line from (8, 0) to (0, 40), which doesn't represent the correct linear relationship.
- Option B reflects a curve, which does not apply since the drain rate is constant.
- Option C indicates a line between (5, 0) and (0, 40), which is a straight line showing the right relationship.
- Option D also shows a curve, which again wouldn't represent a constant drain rate.
Thus, the correct choice is Option C. This graph shows a straight line from 40 gallons at time 0 to 0 gallons at time 5, accurately representing the draining process.