Quadratic Equation Solver

Solve any quadratic equation from coefficients \(a\), \(b\), and \(c\). See real or complex roots instantly and visualize the parabola.

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Quadratic Equation Calculator

Enter coefficients \(a\), \(b\), and \(c\) to solve \(ax^2 + bx + c = 0\)

Must not be zero

Quadratic Equation Graph

The solutions correspond to x-intercepts of the parabola \(y = ax^2 + bx + c\)

Enter coefficients and click "Calculate Solutions" to see the graph

Graph Interpretation:

  • Two x-intercepts → Two distinct real roots
  • One tangent point → Double real root
  • No x-intercepts → Complex conjugate roots

Learn About Quadratic Equations

Quadratic Formula

\(x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\)

The universal formula for solving any quadratic equation.

Learn More

Discriminant

\(D = b^2 - 4ac\)

Determines the nature of roots: real, double, or complex.

Calculate

Parabola Graph

Visual representation of quadratic functions.

Understand roots, vertex, and symmetry through graphing.

Explore

Vertex Form

\(y = a(x - h)^2 + k\)

Alternative form showing vertex \((h, k)\) directly.

Convert

Specialized Quadratic Tools

Factoring Quadratics

Solve by factoring when possible.

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Completing the Square

Step-by-step transformation to vertex form.

Try Tool

Complex Roots

Handle equations with no real solutions.

Try Tool

Word Problems

Applied quadratic equation examples.

Practice

Frequently Asked Questions

What is a quadratic equation? +

A quadratic equation is a polynomial equation of degree 2, typically written in the form \(ax^2 + bx + c = 0\), where \(a\), \(b\), and \(c\) are constants and \(a \neq 0\).

How does the quadratic formula work? +

The quadratic formula \(x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\) provides the solutions to any quadratic equation by substituting the coefficients \(a\), \(b\), and \(c\). The \(\pm\) symbol indicates there are usually two solutions.

What does the discriminant tell us? +

The discriminant \(D = b^2 - 4ac\) determines the nature of the roots:

  • \(D > 0\): Two distinct real roots
  • \(D = 0\): One real double root
  • \(D < 0\): Two complex conjugate roots

Can I solve quadratic equations without the formula? +

Yes! Quadratic equations can also be solved by:

  • Factoring (when factorable)
  • Completing the square
  • Graphical methods
Our specialized tools cover all these methods.

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