How it works
Solves ax² + bx + c = 0 with x = (−b ± √(b² − 4ac)) / (2a). Shows completing-the-square steps, discriminant cases, and parabola features (axis, vertex, intercepts).
x = (−b ± √(b² − 4ac)) / (2a)
When to use
Use this tool when you need to: fractions OK (3/4). Example: a=1, b=−5, c=6 → roots 3 and 2. a cannot be zero.
How to use this tool
- Enter your values in the fields above.
- Review the formula and any mode options for your problem.
- Read the result and the step-by-step solution.
Fractions OK (3/4). Example: a=1, b=−5, c=6 → roots 3 and 2. a cannot be zero.
Frequently asked questions
- What is the Quadratic Formula Calculator?
- Solves ax² + bx + c = 0 with x = (−b ± √(b² − 4ac)) / (2a). Shows completing-the-square steps, discriminant cases, and parabola features (axis, vertex, intercepts).
- How do I use the Quadratic Formula Calculator?
- Enter the required values, then calculate. The Quadratic Formula Calculator shows results, formulas, and step-by-step work when available. No account is required.
- What formula does the Quadratic Formula Calculator use?
- x = (−b ± √(b² − 4ac)) / (2a)
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