\[3x^{2} + x(4 - 3x) = 8\]
\[3x^{2} + 4x - 3x^{2} = 8\]
\[4x = 8\]
\[x = 2.\]
\[x_{1} = 2 \Longrightarrow y_{1} = 4 - 3 \cdot 2 =\]
\[= 4 - 6 = - 2.\]
\[3x^{2} + x( - 4 - 3x) = 8\]
\[3x^{2} - 4x - 3x^{2} = 8\]
\[- 4x = 8\]
\[x = - 2.\]
\[x_{2} = - 2 \Longrightarrow \text{\ \ \ }\]
\[\Longrightarrow \text{\ \ }y_{2} = - 4 - 3 \bullet ( - 2) =\]
\[= - 4 + 6 = 2.\]
\[Ответ:(2;\ - 2),\ \ \ ( - 2;2).\]