Answer:
Cost function C(x) where x is the cubic feet of water used.
[tex]C(x) = 75 + 0.03x[/tex]
Step-by-step explanation:
We are given the following in the question:
The municipal water supply are billed a fixed amount monthly plus a charge for each cubic foot of water used.
Let x be the fixed amount and y be the cost for each cubic foot of water used.
A household using 1700 cubic feet was billed $126.
Thus, we can write:
[tex]x + 1700y = 126[/tex]
A household using 2500 cubic feet was billed $150.
[tex]x + 2500y = 150[/tex]
Solving the two equation by eliminating x by subtracting the equations, we get,
[tex]x+2500y-(x + 1700y) = 150-126\\800y = 24\\\\y =\dfrac{24}{800} = 0.03\\\\x+1700(0.03) = 126\\\Rightarrow x = 126-(1700)(0.03) = 75[/tex]
Thus, the fixed cost is $75 and the cost per cubic foot of water is $0.03
Cost function can be written as:
[tex]C(x) = 75 + 0.03x[/tex]
where x is the cubic feet of water used.
