Quadratic Equation Solver
Solve any quadratic equation ax² + bx + c = 0, including real and complex roots.
Solve ax² + bx + c = 0
How it works
- 1Enter the coefficients a, b, and c.
- 2The discriminant b² − 4ac decides the number and type of roots.
- 3Read two real roots, one repeated root, or a complex conjugate pair.
Use cases
- Solve quadratic equations for algebra homework.
- Find where a parabola crosses the x-axis.
- Check whether roots are real or complex via the discriminant.
Frequently asked questions
What is the quadratic formula?
x = (−b ± √(b² − 4ac)) ÷ 2a. The part under the square root, b² − 4ac, is the discriminant.
What does the discriminant tell me?
If it is positive there are two real roots, if zero there is one repeated root, and if negative the roots are a complex conjugate pair.
What if a is 0?
The equation is linear, not quadratic, so the tool solves bx + c = 0 for the single root x = −c ÷ b.
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