\[3y² - 13y + 4 = 0\ \ \]
\[a = 3,\ \ b = - 13,\ \ c = 4\]
\[D = b^{2} - 4\text{ac} =\]
\[= ( - 13)^{2} - 4 \cdot 3 \cdot 4 =\]
\[= 169 - 48 = 121\]
\[y_{1,2} = \frac{- b \pm \sqrt{D}}{2a}\]
\[y_{1} = \frac{- ( - 13) + \sqrt{121}}{2 \cdot 3} =\]
\[= \frac{13 + 11}{6} = \frac{24}{6} = 4\]
\[y_{2} = \frac{- ( - 13) - \sqrt{121}}{2 \cdot 3} =\]
\[= \frac{13 - 11}{6} = \frac{2}{6} = \frac{1}{3}\]
\[Ответ:y = 4;y = \frac{1}{3}.\]