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Quadratic Formula Calculator

Roots of ax² + bx + c = 0, including complex roots when the discriminant is negative.

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Results

How to use Quadratic Formula Calculator

  1. Enter a, b, c. Leave a field blank only when the page says the value is missing.
  2. Read the result rows under the form. Errors appear in the status line. Nothing is uploaded.
  3. Rounding follows IEEE floating point in this browser unless the page says it uses integers or BigInt.

Quadratic Formula Calculator

Real roots

ComputesRoots of ax² + bx + c = 0, including complex roots when the discriminant is negative.
IncludesReal roots
IncludesComplex roots
Enginepercentage
UploadNone
AdviceArithmetic only

What Quadratic Formula Calculator is

x = (−b ± √(b² − 4ac)) / (2a). a cannot be 0. A negative discriminant returns a ± bi on this page, not a plot.

The formula runs in this tab. CZNull does not receive the numbers.

How this page computes

This is not a CAS. It will not factor a polynomial with leftover x symbols. Exponents of numbers are the exponent page.

Entities and related jobs

Roots of ax² + bx + c = 0, including complex roots when the discriminant is negative. Named features: Real roots, Complex roots.

See also Scientific Calculator, Exponent Calculator, Order of Operations Calculator, Percentage Calculator, Fraction Calculator, GCD Calculator.

Use cases

Projectile equations and school quadratics. Completing the square by hand is not shown as a step list.

Limits

Invalid input appears in the status line. IEEE floating point applies unless a row says otherwise. CZNull does not receive the numbers.

Quadratic Formula Calculator questions

Does this page upload my numbers?
No. The formula runs in the page you opened. CZNull does not receive the values.
What does Quadratic Formula Calculator compute?
x = (−b ± √(b² − 4ac)) / (2a).
Why is this its own URL?
Search queries name this job. Nearby modes stay on their own pages so inputs do not mix. Related calculators are linked below Quadratic Formula Calculator.
Roots of x² − 3x + 2 = 0?
2 and 1.
Negative discriminant?
Complex roots a ± bi, not a plot.
Can I treat the result as official?
No. Rounding and real-world rules can differ. Use the page to check the arithmetic.