2x^2+9x=-5

Use the on-site calculator to get

$${\mathtt{2}}{\mathtt{\,\times\,}}{{\mathtt{x}}}^{{\mathtt{2}}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\times\,}}{\mathtt{x}} = -{\mathtt{5}} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = {\mathtt{\,-\,}}{\frac{\left({\sqrt{{\mathtt{41}}}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}\right)}{{\mathtt{4}}}}\\
{\mathtt{x}} = {\frac{\left({\sqrt{{\mathtt{41}}}}{\mathtt{\,-\,}}{\mathtt{9}}\right)}{{\mathtt{4}}}}\\
\end{array} \right\} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = -{\mathtt{3.850\: \!781\: \!059\: \!358\: \!212\: \!2}}\\
{\mathtt{x}} = -{\mathtt{0.649\: \!218\: \!940\: \!641\: \!787\: \!8}}\\
\end{array} \right\}$$

$$2x^2+9x+5=0$$

or if you need to do it by hand you use the quadratic formula

https://www.youtube.com/watch?v=O8ezDEk3qCg