SOLUTION: Solve the equation by use of the quadratic formula. 3x^2 -5=-4x

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Question 1009868: Solve the equation by use of the quadratic formula.
3x^2 -5=-4x
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the equation by use of the quadratic formula.
3x^2 -5=-4x
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3x^2 + 4x - 5 = 0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 3x%5E2%2B4x%2B-5+=+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=%284%29%5E2-4%2A3%2A-5=76.

Discriminant d=76 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-4%2B-sqrt%28+76+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%284%29%2Bsqrt%28+76+%29%29%2F2%5C3+=+0.786299647846891
x%5B2%5D+=+%28-%284%29-sqrt%28+76+%29%29%2F2%5C3+=+-2.11963298118022

Quadratic expression 3x%5E2%2B4x%2B-5 can be factored:
3x%5E2%2B4x%2B-5+=+%28x-0.786299647846891%29%2A%28x--2.11963298118022%29
Again, the answer is: 0.786299647846891, -2.11963298118022. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+3%2Ax%5E2%2B4%2Ax%2B-5+%29

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