SOLUTION: The monthly cost in dollars) of water use is a linear function of the amount of water used in hundreds of cubic feet, HCF). The cost for using 13 HCF of water is \$31.25 , and the
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-> SOLUTION: The monthly cost in dollars) of water use is a linear function of the amount of water used in hundreds of cubic feet, HCF). The cost for using 13 HCF of water is \$31.25 , and the
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Question 1164111: The monthly cost in dollars) of water use is a linear function of the amount of water used in hundreds of cubic feet, HCF). The cost for using 13 HCF of water is \$31.25 , and the cost for using 39 HCF \$76.75 What is the cost for using 29 HCF of water Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! (13, 31.25)
(39, 76.75)
find the equation of a line with those two points and substitute 29 for x
slope is 45.5/26=1.75
point slope formula y-y1=m(x-x1), m slope, (x1, y1) point
y-31.25=1.75(x-13)
y-31.25=1.75x-22.75
y=1.75x+8.5
when x=29 (HCF)
y=1.75(29)+8.5
=$59.50
