In any equation there is a variable (usually x). In a quadratic equation there is a lot involved.
-B (+or-) sqrt of b^2 - 4 x A x C
________________________ divide it by
2 x A
There is usually an original equation that looks like: Ax^2 + Bx + C = 0 Use the variables from the equation to the left to fill the upper equation. (You can also look up a better formula if confused).