[tex]\begin{gathered} x^2+2x-17=0 \\ \text{let's use the quadratic formula} \\ ax^2+bx+c=0 \\ x=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a} \\ \text{ In this case:} \\ a=1 \\ b=2 \\ c=-17 \end{gathered}[/tex][tex]\begin{gathered} x=\frac{-2\pm\sqrt[]{2^2-(4)(1)(-17)}}{2(1)} \\ x=\frac{-2\pm\sqrt[]{4+68}}{2} \\ x=\frac{-2\pm\sqrt[]{72}}{2} \\ x=\frac{-2\pm6\sqrt[]{2}}{2} \\ ------------- \\ x=-1+3\sqrt[]{2} \\ or \\ x=-1-3\sqrt[]{2} \end{gathered}[/tex]
