How to use this calculator
The quadratic formula solves any second-degree equation with a nonzero x² coefficient.
The method
x = (−b ± √(b²−4ac)) / 2a
Enter your values in the labeled fields and choose Calculate. The result panel shows the answer and supporting values when useful.
WORKED EXAMPLE INPUT
a: 1, b: -5, c: 6
Select Calculate to evaluate these example values.
Scope and limitations
a cannot be zero. Complex roots are reported when the discriminant is negative.
Common questions
Can I use different units?
Use consistent units unless this page is a unit converter. The result follows the units implied by the inputs.
Are results exact?
Displayed values may be rounded. Keep extra precision for important follow-up calculations.
Methods & verification
Formulas use standard mathematical definitions and fixed unit factors where applicable. See our methodology for numerical conventions, rounding, privacy, and limitations.