SOLUTION: 2x^2-1 = 5x

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Question 22368: 2x^2-1 = 5x
Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
Subtract "5x" from each side of the equation to get:
2x^2-5x-1=0
Use the quadratic formula to find "x".
Solved by pluggable solver: SOLVE quadratic equation with variable
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=33 is greater than zero. That means that there are two solutions: .




Quadratic expression can be factored:

Again, the answer is: 2.68614066163451, -0.186140661634507. Here's your graph:

Cheers,
Stan H.
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