x^2+2x-1=9

If you need to solve by hand then use the quadratic formula

http://web2.0calc.com/questions/quadratic-formula-do-you-have-trouble-remembering-it

Write this as x² +2x - 10 = 0 and use the quadratic formula.

$${{\mathtt{x}}}^{{\mathtt{2}}}{\mathtt{\,\small\textbf+\,}}{\mathtt{2}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{10}} = {\mathtt{0}} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = {\mathtt{\,-\,}}{\sqrt{{\mathtt{11}}}}{\mathtt{\,-\,}}{\mathtt{1}}\\
{\mathtt{x}} = {\sqrt{{\mathtt{11}}}}{\mathtt{\,-\,}}{\mathtt{1}}\\
\end{array} \right\} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = -{\mathtt{4.316\: \!624\: \!790\: \!355\: \!399\: \!8}}\\
{\mathtt{x}} = {\mathtt{2.316\: \!624\: \!790\: \!355\: \!399\: \!8}}\\
\end{array} \right\}$$

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x^2+2x-1=9     subtract 9 from both sides

x^2 + 2x - 10 = 0      this can't be factored......let's just use the onsite calculator to solve

$${{\mathtt{x}}}^{{\mathtt{2}}}{\mathtt{\,\small\textbf+\,}}{\mathtt{2}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{10}} = {\mathtt{0}} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = {\mathtt{\,-\,}}{\sqrt{{\mathtt{11}}}}{\mathtt{\,-\,}}{\mathtt{1}}\\
{\mathtt{x}} = {\sqrt{{\mathtt{11}}}}{\mathtt{\,-\,}}{\mathtt{1}}\\
\end{array} \right\} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = -{\mathtt{4.316\: \!624\: \!790\: \!355\: \!399\: \!8}}\\
{\mathtt{x}} = {\mathtt{2.316\: \!624\: \!790\: \!355\: \!399\: \!8}}\\
\end{array} \right\}$$