Answer:
y = 52x + 400
Step-by-step explanation:
A linear model has the form y = mx + b
There are two variables: the volume (y) of water and the number (x) of minutes the pool has been filling. The volume of water depends on how long the pool is filling.
m = (y₂-y₁)/(x₂ -x₁)
x₁ = 0; y₁ = 400
x₂ = 8; y₂ = 816
m = (816 - 400)/(8 - 0)
m = 416/8
m = 52 gal/min
The initial value (b) is the volume at time zero.
b = 400 gal
The linear function is
y = 52x + 400
===============
Volume after 20 min
y = 52×20 + 400
y = 1040 + 400
y = 1440 gal
The pool will contain 1440 gal in 20 min.
