Quadratic Equation Solver
Use this step by step quadratic equation solver to see the discriminant, the type of roots and the working for ax² + bx + c = 0.
Roots
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How it works
Discriminant D = b² - 4ac. Roots x = (-b ± √D) / 2a.How to use the Quadratic Equation Solver
Enter the coefficients a, b and c. The tool shows the discriminant and the roots, then explains whether the roots are real, repeated or complex.
Use the displayed working to check the quadratic formula. Keep the coefficients in the same equation and check that a is not zero when you need a quadratic result.
Frequently Asked Questions
What does the discriminant tell me?
If D > 0 there are two real roots, if D = 0 there is one repeated real root, and if D < 0 the roots are a complex conjugate pair.
What information should I enter?
Use the input labels as a guide and enter figures from the same situation, time period and units wherever possible.
Can I use the result as an exact answer?
Treat it as an estimate or check unless the page and the rules that apply to you confirm otherwise. Rounding, fees and personal details can change the final result.