Quadratic Equation Solver: Roots, Discriminant and Vertex

What is it?

The Quadratic Equation Solver solves equations of the form ax² + bx + c = 0. It shows the roots, the discriminant (b² − 4ac), what kind of roots they are, and the vertex of the curve.

Who is it for?

Class 9–12 students, teachers checking answers, and anyone solving second-degree equations.

How to use it

Enter a, b and c. Bring the equation to the form ax² + bx + c = 0 first: x² = 5x − 6 becomes x² − 5x + 6 = 0, so a = 1, b = −5, c = 6. The answer appears as you type; there is no Calculate button. Tap Copy result to copy it, or Share on WhatsApp to send it.

What the discriminant tells you

  • Positive: two different real roots (the graph crosses the x-axis twice).
  • Zero: one repeated root (the graph touches the axis).
  • Negative: no real roots; two complex roots like 2 ± 3i.

The vertex

The highest or lowest point of the parabola, at x = −b ÷ 2a. If a is positive, it is the lowest point (minimum).

Common mistakes

  • Forgetting the sign: for x² − 5x + 6, b is −5, not 5.
  • a can’t be 0: then it isn’t quadratic. Solve bx + c = 0 instead.
  • A missing term means 0: for x² − 9 = 0, b = 0.

Formula: x = (−b ± √(b² − 4ac)) ÷ 2a.

Errors and how to fix them

  • “a cannot be 0 (then it is not quadratic)”: solve bx + c = 0 instead.

Open the tool: Quadratic Equation Solver

Still stuck?

Contact support. Tell us which tool or page you were using, what you tapped, what you saw, and your phone or computer and browser (for example: Android phone, Chrome). We reply by email.

Questions, or an error not listed here?

Tell us in the comments: what you were doing, the exact message you saw, and your device and browser. We read every comment and add new fixes to this article.