Quadratic Formula Calculator
Solve ax² + bx + c = 0, including complex roots and the vertex. The result updates as you type, with the working underneath so you can check it.
Your details
Result
Solutions
x = 1, x = 2
two real roots
- Discriminant (b² − 4ac)
- 1
- Vertex
- (1.5, -0.25)
Good to know: x = (−b ± √(b² − 4ac)) ÷ 2a
About this tool
Formula
x = (−b ± √(b² − 4ac)) ÷ 2a
Questions people ask
What does the discriminant tell me?
If b² − 4ac is positive there are two real roots, zero gives one repeated root, and negative gives two complex roots.
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How we calculate this
We use the standard published formula or definition for this calculation, and we show the working so you can check it.
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