Quadratic Equation Solver
Roots, discriminant and vertex of any quadratic equation.
Frequently Asked Questions
What is the quadratic formula?
x = (-b ± √(b² - 4ac)) / 2a. It solves every quadratic equation ax² + bx + c = 0 directly from its coefficients, with no factoring or guessing needed.
What does the discriminant tell you?
The discriminant b² - 4ac decides the root type before you solve: positive means two real roots, zero means one repeated root, and negative means two complex roots involving i, the square root of -1.
How do I find the vertex?
The vertex x-coordinate is -b / 2a, which is also the axis of symmetry. Substitute that x back into the equation to get the y-coordinate, the minimum or maximum value of the parabola.
Is the Quadratic Equation Solver free, and is my data private?
Yes. It is completely free and every calculation runs locally in your browser, so the numbers and dates you enter are never uploaded, stored, or shared with anyone.
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