SOLUTION: I need help solving this problem. I keep getting the wrong answer. 5=.0002x^2-.316x+127.9. If you could help I would greatly appriciate it.

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: I need help solving this problem. I keep getting the wrong answer. 5=.0002x^2-.316x+127.9. If you could help I would greatly appriciate it.      Log On


   

Question 341023: I need help solving this problem. I keep getting the wrong answer. 5=.0002x^2-.316x+127.9. If you could help I would greatly appriciate it.
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
5=.0002x^2-.316x+127.9
0.0002x%5E2+-+0.316x+%2B+112.9+=+0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 0.0002x%5E2%2B-0.316x%2B112.9+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%28-0.316%29%5E2-4%2A0.0002%2A112.9=0.00953599999999999.

Discriminant d=0.00953599999999999 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--0.316%2B-sqrt%28+0.00953599999999999+%29%29%2F2%5Ca.




Quadratic expression 0.0002x%5E2%2B-0.316x%2B112.9 can be factored:
0.0002x%5E2%2B-0.316x%2B112.9+=+%28x-1034.13111231467%29%2A%28x-545.868887685326%29
Again, the answer is: 1034.13111231467, 545.868887685326. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+0.0002%2Ax%5E2%2B-0.316%2Ax%2B112.9+%29

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Ignore the part about factoring it.