\[x² - 2|x| - 8 = 0\]
\[D = ( - 2)^{2} - 4 \cdot 1 \cdot ( - 8) =\]
\[= 4 + 32 = 36\]
\[x_{1} = \frac{2 + \sqrt{36}}{2} = \frac{2 + 6}{2} = \frac{8}{2} = 4\]
\[x_{2} = \frac{2 - \sqrt{36}}{2} = \frac{2 - 6}{2} = - \frac{4}{2} =\]
\[= - 2\ (не\ подходит)\]
\[x^{2} + 2x - 8 = 0\]
\[D = 2^{2} - 4 \cdot 1 \cdot ( - 8) =\]
\[= 4 + 32 = 36\]
\[x_{1} = \frac{- 2 + \sqrt{36}}{2} = \frac{- 2 + 6}{2} =\]
\[= \frac{4}{2} = 2\ (не\ подходит)\]
\[x_{2} = \frac{- 2 - \sqrt{36}}{2} = \frac{- 2 - 6}{2} =\]
\[= - \frac{8}{2} = - 4\]
\[Ответ:\ - 4;4.\]