The Bridgeport water department has a monthly service charge of $12.90 and a usage charge of $1.57 for every 100 cubic feet of water. Which of the following equations can be used to determine the monthly water bill of a Bridgeport resident? (Let x represent the amount of water used in hundreds of cubic feet and y represent the monthly cost.)
A.
y = 1.57x + 12.90
B.
y = 1.57x - 12.90
C.
y = 14.47x
D.
y = 0.0157x + 12.90
Monthly the rate of just having the service does not change, so 12.90 would be added to the product of the rate for so much water, 1.57, and how much water was used, X. The equation ends up with y= 1.57X + 12.90 :A
