\[0,5x^{2} - x - 1 = 0\ \ \ \ \ | \cdot 2\]
\[x^{2} - 2x - 2 = 0\]
\[D = 1 + 2 = 3\]
\[x_{1} = 1 + \sqrt{3};\ \ x_{2} = 1 - \sqrt{3}.\]