\[( - x - 1)(x - 4) = x(4x - 11)\]
\[- x^{2} + 4x - x + 4 = 4x^{2} - 11x\]
\[- x^{2} + 3x + 4 - 4x^{2} + 11x = 0\]
\[- 5x^{2} + 14x + 4 = 0\ \ \ \ | \cdot ( - 1)\]
\[5x^{2} - 14x - 4 = 0\]
\[D = b^{2} - 4ac =\]
\[= 196 - 4 \cdot 5 \cdot ( - 4) =\]
\[= 196 + 80 = 276\]
\[x_{1} = \frac{14 + 2\sqrt{69}}{10} = \frac{7}{5} + \frac{\sqrt{69}}{5}\]
\[x_{2} = \frac{14 - 2\sqrt{69}}{10} = \frac{7}{5} - \frac{\sqrt{69}}{5}\]
\[Ответ:x = \frac{7}{5} + \frac{\sqrt{69}}{5}\ \ \ и\ \ \ \]
\[x = \frac{7}{5} - \frac{\sqrt{69}}{5}.\]