What if the discriminant is negative?

A negative discriminant means the equation has no real roots — only complex roots, which this calculator does not display.

Quadratic Equation Solver

Enter the coefficients a, b, and c of a quadratic equation to find its real roots, along with the discriminant.

Inputs

Results

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Formula

x = (−b ± √(b² − 4ac)) / 2a

Core Math Formulas Everyone Should Know (With Real Examples)

Percentages, the quadratic formula, and the Pythagorean theorem explained with step-by-step worked examples.

The Quadratic Formula, Explained Step by Step

How to solve any quadratic equation using the quadratic formula, including what a negative discriminant actually means.

Percentage Calculator

Find what percentage one number is of another, or calculate percentage change.

Percentage Change Calculator

Calculate the percentage increase or decrease between two values.

Average (Mean) Calculator

Calculate the average of up to 10 numbers.

Standard Deviation Calculator

Calculate the population standard deviation of up to 5 numbers.

Circle Area & Circumference Calculator

Calculate the area, circumference, and diameter of a circle from its radius.

Triangle Area Calculator

Calculate a triangle's area from three side lengths using Heron's formula.