Quadratic equation · real roots
Calculate quadratic equation · real roots and see the working behind your result.
Inputs
Use the units shown—
Enter your values and select Calculate.
Formula & explanation
x = (−b ± √(b²−4ac))/(2a)
Variables & units
- Coefficient of x²
- Numeric value · minimum -1000000, maximum 1000000
- Coefficient of x
- Numeric value · minimum -1000000, maximum 1000000
- Constant
- Numeric value · minimum -1000000, maximum 1000000
Worked example
x²−5x+6=0 has roots 2 and 3.
Assumptions
Numerical evaluation uses an equivalent stable root formula. Repeated roots are displayed twice.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
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