Answer:
5 hours
Explanation:
Let's express each scenario as a function in a slope-intercept form, y = mx + b,
Where,
y = total amount of water
x = number of hours
m = rate of at which water is drained or filled per hour
b = initial quantity of water in the tank
✔️Equation for Tank A:
m = 2 gallons/hour = 2
b = 100 gallons = 100
Substitute m = 2 and b = 100 into y = mx + b:
y = 2x + 100
✔️Equation for Tank B:
m = 6 gallons/hour = -6 (this is negative 6 because water drains)
b = 140 gallons = 140
Substitute the values into y = mx + b
y = -6x + 140
✔️Set the two equation equal together to determine the number of hours (x) that must pass for the total amount of water (y) in tank A and tank B to be the same.
2x + 100 = -6x + 140
Collect like terms
2x + 6x = -100 + 140
8x = 40
Divide both sides by 8
x = 40/8
x = 5
Therefore, 5 hours must pass for the total amount of water in both tanks to be the same.