[tex]\displaystyle\bf\\\left \{ {{y=-\dfrac{4}{x} } \atop {y=-x}} \right. \\\\\\\left \{ {{-x=-\dfrac{4}{x} } \atop {y=-x}} \right. \\\\\\\left \{ {{-x+\dfrac{4}{x}=0 } \atop {y=-x}} \right. \\\\\\\left \{ {{\dfrac{-x^{2} +4}{x}=0 } \atop {y=-x}} \right. \\\\\\\left \{ {{\dfrac{x^{2} -4}{x}=0 } \atop {y=-x}} \right. \\\\\\\left \{ {{\dfrac{(x -2)(x+2)}{x}=0 } \atop {y=-x}} \right.\\\\\\\left \{ {{\left[\begin{array}{ccc}x-2=0\\x+2=0\end{array}\right } \atop {y=-x}} \right.[/tex]

[tex]\displaystyle\bf\\\left \{ {{\left[\begin{array}{ccc}x_{1} =2\\x_{2} =-2\end{array}\right } \atop {y=-x}} \right. \\\\\\\left[\begin{array}{ccc}\left \{ {{x_{1} =2} \atop {y_{1} =-2}} \right. \\\left \{ {{x_{2} =-2} \atop {y_{2} =2}} \right. \end{array}\right\\\\\\Otvet \ : \ a) \ \ (2 \ ; \ -2) \ \ , \ \m (-2 \ ; \ 2)[/tex]