$$ \begin{aligned} x^2+6x &= -9&& \text{move all terms to the left hand side } \\[1 em]x^2+6x+9 &= 0&& \\[1 em] \end{aligned} $$
$ x^{2}+6x+9 = 0 $ is a quadratic equation.
You can use step-by-step quadratic equation solver to see a detailed explanation on how to solve this equation.
This page was created using
Equations Solver