What is the quadratic formula?

x = (-b ± √(b²-4ac)) / 2a. It finds the roots of any quadratic equation ax² + bx + c = 0.

What does the discriminant tell us?

D > 0: two real roots. D = 0: one double root. D < 0: two complex roots.

The vertex is the maximum or minimum point of the parabola at x = -b/(2a).

Last Updated: April 13, 2026

Free quadratic equation solver. Find roots, vertex, and discriminant of ax² + bx + c = 0.

a (x² coefficient)

b (x coefficient)

c (constant)

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