 Quadratic formula

For a quadratic equation $a{x}^2+bx+c=0$ with $a\ne 0$, completing the square givesOver the complex numbers both roots exist, with a repeated root of a polynomial when the discriminant $b^2-4ac$ is zero. Over the real numbers the discriminant determines whether there are two distinct roots, one repeated root, or no real root.

The quadratic formula is a mathematical formula used to find the solutions (or roots) of a quadratic equation, which is typically written in the standard form: \[ ax^2 + bx + c = 0 \] where \( a \), \( b \), and \( c \) are coefficients, and \( a \neq 0 \).