What is Quadratic Formula Calculator?
The quadratic formula provides the analytic solutions to any second-degree polynomial equation ax² + bx + c = 0, determining where the parabola crosses the x-axis.
How to Use This Calculator
- Enter coefficients a, b, and constant c.
- The tool evaluates the discriminant (b² - 4ac).
- Examine roots (real or imaginary) and graph vertex coordinates.
The Mathematical Formula & Variables
x = (-b ± Sqrt(b^2 - 4*a*c)) / (2*a)
Variables Definition
| Symbol / Variable | Name | Description |
|---|---|---|
Δ |
Discriminant | b² - 4ac determines root nature (>0 real distinct, =0 duplicate, <0 complex). |
Step-by-Step Worked Example
Scenario: Solve x² + x - 6 = 0 (a=1, b=1, c=-6).
- Discriminant = 1² - 4(1)(-6) = 1 + 24 = 25.
- √25 = 5.
- xâ‚ = (-1 + 5) / 2 = 4 / 2 = 2.
- xâ‚‚ = (-1 - 5) / 2 = -6 / 2 = -3.
Result: x = 2 or x = -3
Frequently Asked Questions
What happens when the discriminant is negative?
When b² - 4ac < 0, the equation has no real solutions. Instead, it yields two complex conjugate roots involving the imaginary unit i (where i = √-1).