SOLUTION: An engineer takes 1 hour longer to do a job than the other engineer. Working together they can finalize a job in 5 hours. How long would it take for each of them to do the job alon

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Question 22479: An engineer takes 1 hour longer to do a job than the other engineer. Working together they can finalize a job in 5 hours. How long would it take for each of them to do the job alone?
Answer by stanbon(64) (Show Source):
Assume the 1st engineer can do the job in "x" hours.
Then each hour he is doing 1/x of the job.
The 2nd engineer does the job in "x+1" hours.
So each hour he is doing 1/(x+1) of the job.
Equation:
They work together for 5 hours and get the job done so
5[(1/x) +(1/(x+1)] = 1 job
Solve for x and x+1.
I understand so far but I cannot get past this .....
x^2-9x+5, I cannot factor it down so I can get the answer.

Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
I think it is x^2-9x-5=0

Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)

Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.

First, we need to compute the discriminant : .

Discriminant d=101 is greater than zero. That means that there are two solutions: .

Quadratic expression can be factored:

Again, the answer is: 9.52493781056044, -0.524937810560445. Here's your graph:

Cheers,
Stan H.