5 + x/4 = 9 where x represents time in minutes
Now we solve for x
5 + x/4 = 9
Subtract 5 on both sides
X/4 = 4
Multiply both sides by 4
X = 4(4)
X = 16
Therefore, it will take 16 minutes to fill up the bucket to a total of 9 gallons.
I hope this Helps!