Quadratic Equation Solver
Enter a, b and c to solve any quadratic equation, including equations with complex roots.
Runs in your browser. Nothing is uploaded Free, no sign-up Works on mobile
Two real roots
x = 3, 2
1x² − 5x + 6 = 0
Discriminant (b² − 4ac)
1
Vertex
(2.5, -0.25)
Sum of roots (−b/a)
5
Product of roots (c/a)
6
x = (−b ± √(b² − 4ac)) / 2a
How to use Quadratic Equation Solver
- Enter the coefficients a, b and c.
- Read the roots and the nature of the roots.
- Use the discriminant and vertex for graphing.
Frequently asked questions
What is the quadratic formula?
x = (−b ± √(b² − 4ac)) ÷ 2a. The expression b² − 4ac is called the discriminant.
What does the discriminant tell you?
If it is positive there are two real roots, if it is zero there is one repeated root, and if it is negative the roots are complex.
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