1. ## Polynomial question help

Hey all. Just joined this forum to look for hopefully some guidance where I have none.

Have a younger brother in the 11th grade taking pre-calc. He presented me a worksheet last night with a word question and 5 questions pertaining the word question. After looking this up and down getting 2 headaches I figured I would turn to a forum for some help.

I think I might have solved question 1, but I am not sure. So here we go with the question.

Four computers working together can upload a large file in 5 hours. One computer can upload the file in 3 less hours than the slowest computer; another can upload in 2 hours less than the slowest computer; and another can upload in 1 hour less than the slowest computer. Your goal is the find the time required for each computer to upload the file without help from the other three computers.

1) write polynomial function that modeal the work of all four computers uploading the file.

This question one if my headache... I think I actually did it using negative when the numbers should of been positive. Anyways Just need help with the first question as the rest should move once I get this established.

Here is what I came up with as the solution:
x(x-3)(x-2)(x-1) = x^4 - 9x^3 + 23x^2 +15x
but it says this equals 5 so then I subtract 5 to both side to keep it set to 0 giving me this equation:
x^4 - 9x^3 + 23x^2 +15x-5 = 0
There are no roots for this.

So I thinking maybe I need to set this equation like such x^4 - 9x^3 + 23x^2 +15x = 5 and solve from here?

Or am I completely in left field roaming aimlessly?

Thanks for your help as I have to attempt to help tonight.

Thanks again!

2. anyone? could really use the help here. Haven't done this type of problem since High school.

Thanks all!