Решите систему уравнений: x-y=4; xy=12.

\[\left\{ \begin{matrix} x - y = 4 \\ xy = 12\ \ \ \\ \end{matrix} \right.\ \]

\[\left\{ \begin{matrix} x = 4 + y\ \ \ \ \ \ \ \ \\ (4 + y)y = 12 \\ \end{matrix} \right.\ \]

\[y^{2} + 4y - 12 = 0\]

\[D_{1} = 4 + 12 = 16\]

\[y_{1} = - 2 + 4 = 2;\ \]

\[y_{2} = - 2 - 4 = - 6.\]

\[x_{1} = 4 + 2 = 6;\ \]

\[x_{2} = 4 - 6 = - 2.\]

\[Ответ:(6;2);( - 2;\ - 6).\]