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cgott
Sep 16, 2010, 02:04 PM
a house 2 miles from the road wants cable. The cable stops 18 miles from the home. The cost to run it above ground is 3000.00 per mile and 4800.00 per mile.

the question asks to create a function to express the total cost indollars of installation as a function of the distance x.
I need to generalize and compute the cost if the wire above ground is x miles long

can some one please help. I am in college algebra (functions) Thanks

cgott
Sep 16, 2010, 02:05 PM
Sorry the 4800.00 is for below ground installation

morgaine300
Sep 17, 2010, 12:45 AM
Are you implying the $4800 is fixed then? I don't see how being below ground would change the fact that it's per mile.

Generally a cost function consists of both variable and fixed. Can you check exactly what the problem says?

Unknown008
Sep 17, 2010, 08:53 AM
Distance of line = 18 miles.

Cost for overhead cables = 18 x 3000 = $54000
Cost for underground cables = 18 x 4800 = $86400

So, if the cable was for x miles, what is the cost, in terms on x, given the information I just gave you?