Quadratic Equation Calculator

Solve ax² + bx + c = 0 instantly, including complex roots and the discriminant.

a (x² coefficient)

b (x coefficient)

c (constant)

First root (x₁)

Last updated: 2026-08-30

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FAQ

What is the quadratic formula?

For ax² + bx + c = 0, the roots are x = (−b ± √(b² − 4ac)) / (2a) — this tool applies it directly.

What does the discriminant tell me?

Positive means two real roots, zero means one repeated root, and negative means two complex conjugate roots.

What if a equals zero?

Then the equation is linear, not quadratic; the calculator flags it instead of dividing by zero.

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