Quadratic Equation Calculator
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Quadratic Equation Calculator

Free Quadratic Equation Calculator: Solve quadratic equations (ax² + bx + c = 0) for real or complex roots and find the discriminant.

Inputs

Enter the required values to calculate.

ax² + bx + c = 0

Result

The calculated result will appear here.

Enter values and click calculate to see the result.

More Information

Understanding the Quadratic Equation Calculator

A quadratic equation is a second-degree polynomial equation in a single variable 'x' of the form ax² + bx + c = 0, where 'a' cannot be zero. This calculator is a powerful tool to solve these equations instantly.

How It's Solved: The Quadratic Formula

The roots (solutions for 'x') are found using the well-known quadratic formula:

x = [-b ± sqrt(b² - 4ac)] / 2a

The Discriminant (b² - 4ac)

The part of the formula under the square root, b² - 4ac, is called the discriminant. It's a critical value because it tells us the nature of the roots without fully solving the equation:

  • If the discriminant is **positive**, there are two distinct real roots.
  • If the discriminant is **zero**, there is exactly one real root (a "repeated root").
  • If the discriminant is **negative**, there are two complex roots (involving imaginary numbers).

Our calculator finds the discriminant and then proceeds to calculate the roots, handling all three cases correctly.

Frequently Asked Questions