The Quadratic Formula
x = (−b ± √(b² − 4ac)) / 2a
Quadratic Equation Calculator
Solve ax² + bx + c = 0 with the quadratic formula. Step-by-step work shown.
x² +
x +
= 0
📐 How We Calculate — Learn about our calculation methodology, data sources, and quality standards.
Frequently Asked Questions
What is the quadratic formula?
x = (−b ± √(b² − 4ac)) / 2a. Works for any ax² + bx + c = 0.
What is the discriminant?
b² − 4ac. Positive = 2 real roots. Zero = 1 root. Negative = complex roots.
What if a = 0?
Then it's linear (bx + c = 0) and x = −c/b.