ALGEBRA / CALCULATOR
Quadratic Equation Calculator.
Solve ax² + bx + c = 0, including complex roots.
LET’S WORK IT OUT
Your numbers, your answer.
THE WHY BEHIND THE ANSWER
How it works.
The discriminant b² − 4ac tells you whether there are two real roots, one repeated root or two complex conjugate roots.
THE FORMULAx = (−b ± √(b² − 4ac)) ÷ 2a
Worked example
For x² − 5x + 6 = 0, the discriminant is 1 and the roots are 2 and 3.
Good to know
When a is zero, the equation is linear instead. This tool handles that case too.
ONE MORE THING
What if the discriminant is negative?
The equation has two complex conjugate roots. Their imaginary parts have equal magnitude and opposite signs.