a (x² coefficient)
b (x coefficient)
c (constant)
Result (click to copy)
Frequently Asked Questions
What is a quadratic equation?
A quadratic equation has the form ax² + bx + c = 0, where a ≠ 0. The highest power of x is 2. They appear in physics (projectile motion), engineering, finance (break-even analysis), and many real-world problems.
What is the discriminant?
The discriminant is b² - 4ac. If positive: two distinct real roots. If zero: one repeated root. If negative: two complex (imaginary) roots. The discriminant tells you how many solutions exist before solving.
What is the quadratic formula?
x = (-b ± √(b² - 4ac)) / 2a. This formula always works for any quadratic equation. The ± means you get two solutions: one with + and one with −.