This table shows the linear relationship of the water level in a tank and time.
Time (hr) Water level (ft)
0 50
2 40
4 30
6 20
Enter the rate of change of the water level, in feet per hour.
The rate of change of the water level can be calculated by finding the slope of the line connecting two points on the graph.
Using the formula for slope:
Rate of change = (change in y-coordinate) / (change in x-coordinate)
Between points (0, 50) and (2, 40), there is a decrease of 10 feet in the water level over a span of 2 hours.
Rate of change = (40 - 50) / (2 - 0)
= -10 / 2
= -5 feet per hour
Therefore, the rate of change of the water level is -5 feet per hour.