Question

7. The Bedrock water department has a monthly service charge of $9.80 and a volume charge of $1.47 for every 100 cubic feet of water. Which of the following equations can be used to determine the Sandstone family's monthly water bill?

(Let x represent 100 cubic feet of water and y represent the monthly cost.)
y = 1.47x - 9.80
y = 11.27x
y = 0.0147x + 9.80
y = 1.47x + 9.80

Answer 1

if you dont use water at all you will pay 9.80
so 9.8 should be positive
so for x = 0 we should have 9.8
so the second and first answers cant be true.

now for every 100 cubic feet of water you will pay 1.47
since x represent a multiplication of 100 cubic feet of water the answer is
y = 1.47x + 9.8

Answer 2

thanks