Question

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

−1/40
gal./hr.
negative Start Fraction 1 over 40 End Fraction gal./hr.

−40
gal./hr.
negative 40 gal./hr.

1/40
gal./hr.
Start Fraction 1 over 40 End Fraction gal./hr.

40 gal./hr.
40 gal./hr.

Answer 1

Slope = (80 − 160)/(3 − 1) = −80/2 = −40, so the pool is losing 40 gallons per hour. Answer: −40 gal/hr.