Question

W

sumate the amount of money she pays, in dollars, when using k kilowatt hours of electricity. She

looks at her previous power bills and finds that she paid $45.83 for 550 kilowatt hours of electricity in November

and $93.57 for 1250 kilowatt hours of electricity in September. She pays the same amount for every kilowatt hour of

electricity

Which function C(k) models the amount Liana will pay for using k kilowatt hours of electricity in one month

Answer 1

`C(k) = 0.0682k + 8.32`

Explanation:

We have to find the function C(k) that models the amount Liana will pay for using k kilowatt-hours of electricity in one month.

Now, the ordered pair for the month of November and September are (550,45.83) and (1250,93.57) respectively.

Since she pays the same amount for every kilowatt-hour of electricity, so the function will be linear.

Hence, the equation can be written as

`(C(k) - 93.57)/(93.57 - 45.83) = (k - 1250)/(1250 - 550)`

⇒
`(C(k) - 93.57)/(47.74) = (k - 1250)/(700)`

⇒
`C(k) - 93.57 = 0.0682k - 85.25`

⇒
`C(k) = 0.0682k + 8.32`

Therefore, this is the function. (Answer)