Quadratic Equation Solver
Solve ax² + bx + c = 0, with the discriminant and steps.
What is a quadratic equation solver?
A quadratic equation solver finds x in ax² + bx + c = 0 using the quadratic formula. Example: x² – 5x + 6 = 0 has roots x = 2 and x = 3.
How to use it
Enter a, b and c, then tap Solve.
Formula
The quadratic formula is x = (-b ± √(b² – 4ac)) ÷ (2a). The discriminant b² – 4ac tells you how many real roots there are: positive means two roots, zero means one root, and negative means no real roots.
Example
For x² – 5x + 6 = 0, the discriminant is (-5)² – 4 × 1 × 6 = 25 – 24 = 1. Then x = (5 ± √1) ÷ 2, so x = 3 or x = 2. Check: 2² – 5 × 2 + 6 = 4 – 10 + 6 = 0, and 3² – 5 × 3 + 6 = 9 – 15 + 6 = 0.
Frequently Asked Questions
What are the roots of x² – 5x + 6 = 0?
x = 2 and x = 3.
What if the discriminant is 0?
There is one repeated root.
What if the discriminant is negative?
There are no real roots.
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