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 14 HCF of water is $33.79, and the cost for using 27 HCF is $55.24. What is the cost for using 18 HCF of water?

The cost of using 18 HCF = $40.39

Step-by-step explanation:

A linear function is one that has a constant rate of change for all the values within the distribution. For a linear function, there is a constant, and that constant is known as the slope or gradient of the linear function.

Let us first calculate this constant (slope).

Let:

X₁ = 14 HCF, Y₁ = $33.79, X₂ = 27 HCF, Y₂ = $55.24, m = slope

at any two points on the linear function, the rate of change of the cost to HCF = 1.65

Now, Let X₃ = 18 HCF, Y₃ = cost for using 18 HCF

Therefore, the cost of using 18 HCF = $40.39

N:B X₂ and Y₂ can also be used with X₃ and Y₃ to find Y₃. You can try it out, you should get the same result

c: y > - 1/6x + 1

step-by-step explanation:

dashed line - meaning this < or > also not equal

solid line - meaning this < or > also equal

your answer is c because y > means up & it's shaded up, but y < means down

hope this ! : )