x2 +0.17x - 1.81*10^-4=0

You can use the quadratic formula to solve this; or just use the solver here:

$${{\mathtt{x}}}^{{\mathtt{2}}}{\mathtt{\,\small\textbf+\,}}{\mathtt{0.17}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{1.81}}{\mathtt{\,\times\,}}{{\mathtt{10}}}^{-{\mathtt{4}}} = {\mathtt{0}} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = {\mathtt{\,-\,}}{\frac{\left({\mathtt{23}}{\mathtt{\,\times\,}}{\sqrt{{\mathtt{14}}}}{\mathtt{\,\small\textbf+\,}}{\mathtt{85}}\right)}{{\mathtt{1\,000}}}}\\ {\mathtt{x}} = {\frac{\left({\mathtt{23}}{\mathtt{\,\times\,}}{\sqrt{{\mathtt{14}}}}{\mathtt{\,-\,}}{\mathtt{85}}\right)}{{\mathtt{1\,000}}}}\\ \end{array} \right\} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = -{\mathtt{0.171\: \!058\: \!119\: \!895\: \!800\: \!7}}\\ {\mathtt{x}} = {\mathtt{0.001\: \!058\: \!119\: \!895\: \!800\: \!7}}\\ \end{array} \right\}$$

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