SOLUTION: Quadratic formula: 3x^2-2x+6=9x+2 x^2+x+5=0 I am a little confused as to how I get the correct answer!

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Question 410205: Quadratic formula:
3x^2-2x+6=9x+2
x^2+x+5=0
I am a little confused as to how I get the correct answer!

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
3x^2-2x+6=9x+2
3x^2 - 11x + 4 = 0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 3x%5E2%2B-11x%2B4+=+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=%28-11%29%5E2-4%2A3%2A4=73.

Discriminant d=73 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--11%2B-sqrt%28+73+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-11%29%2Bsqrt%28+73+%29%29%2F2%5C3+=+3.25733395755292
x%5B2%5D+=+%28-%28-11%29-sqrt%28+73+%29%29%2F2%5C3+=+0.409332709113745

Quadratic expression 3x%5E2%2B-11x%2B4 can be factored:
3x%5E2%2B-11x%2B4+=+%28x-3.25733395755292%29%2A%28x-0.409332709113745%29
Again, the answer is: 3.25733395755292, 0.409332709113745. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+3%2Ax%5E2%2B-11%2Ax%2B4+%29

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x^2+x+5=0
Do it the same way.