\[3x^{2} - 2x - 5\]
\[D = ( - 2)^{2} - 4 \cdot 3 \cdot ( - 5) =\]
\[= 4 + 60 = 64\]
\[x_{1} = \frac{2 + \sqrt{64}}{2 \cdot 3} = \frac{2 + 8}{6} = \frac{10}{6} =\]
\[= \frac{5}{3} = \frac{5}{3}\]
\[x_{2} = \frac{2 - \sqrt{64}}{2 \cdot 3} = \frac{2 - 8}{6} = \frac{- 6}{6} =\]
\[= - 1\]
\[3x^{2} - 2x - 5 =\]
\[= 3 \bullet \left( x - \frac{5}{3} \right)(x + 1) =\]
\[= (3x - 5)(x + 1)\]