\[- x^{2} - x + 6 = 0\]
\[x^{2} + x - 6 = 0\]
\[x_{1} + x_{2} = - 1;\ \ x_{1} \cdot x_{2} = - 6\]
\[x_{1} = 2,\ \ x_{2} = - 3\]
\[- x^{2} - x + 6 = - (x - 2)(x + 3).\]
\[x^{2} - 7x + 10 = 0\]
\[x_{1} + x_{2} = 7;\ \ \ x_{1} \cdot x_{2} = 10\]
\[x_{1} = 5,\ \ x_{2} = 2\]
\[x² - 7x + 10 = (x - 5)(x - 2).\]