SOLUTION: Suppose that a household's monthly water bill (in dollars) is a linear function of the amount of water the household uses (in hundreds of cubic feet, HCF). When graphed, the funct

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: Suppose that a household's monthly water bill (in dollars) is a linear function of the amount of water the household uses (in hundreds of cubic feet, HCF). When graphed, the funct      Log On


   

Question 204191: Suppose that a household's monthly water bill (in dollars) is a linear function of the amount of water the household uses (in hundreds of cubic feet, HCF). When graphed, the function gives a line with a slope of 1.35.
If the monthly bill fro 16 HCF is $24.35, what is the monthly bill for 20 HCF?
I know that linear functions are x+y=z, I need help setting up the problem. Could you please help me!!!???!!!
z(monthly cost)= x(HCF)+ y or
monthly bill=1.35x + 20 or
20=1.35x + y PLEASE HELP!!
Question is not from a book...it's a quiz question.
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the slope (1.35) is the cost (in dollars) of one HCF of water

20 HCF is 4 more than 16 HCF so the cost will be 4 * 1.35 or $5.40 more

$24.35 + $5.40 = $29.75

yes, you could find the function ___ but it isn't necessary