The graph shows the number of gallons in a wading pool that is being drained. Using the points (1,160) and (3,80) as (x1,y1) and (x2,y2), what is the rate of change in the number of gallons in the pool after each hour has passed?
(1 point)
Responses
140 gal./hr.
Start Fraction 1 over 40 End Fraction gal./hr.
−40 gal./hr.
negative 40 gal./hr.
−140 gal./hr.
negative Start Fraction 1 over 40 End Fraction gal./hr.
40 gal./hr.
To find the rate of change in the number of gallons in the pool after each hour has passed, we need to calculate the slope of the line passing through the points (1,160) and (3,80).
Slope = (y2 - y1) / (x2 - x1)
Slope = (80 - 160) / (3 - 1)
Slope = (-80) / 2
Slope = -40
Therefore, the rate of change in the number of gallons in the pool after each hour has passed is -40 gal/hr.