Відповідь:
\begin{equation}1)\left\{\begin{matrix}
|x|=|y|,\\ y=-\frac{x}{2}+\frac{3}{2};
\end{matrix}\right.
\end{equation}
\begin{equation}x_{1}=-3; y_{1}=3;\end{equation}
\begin{equation}x_{2}=1;y_{2}=1;\end{equation}
\begin{equation}2)\left\{\begin{matrix}
y=2x-3,y=2x+3,\\ y=\frac{x}{2};
\end{matrix}\right.
\end{equation}
\begin{equation}x_{1}=-2; y_{1}=-1;\end{equation}
\begin{equation}x_{2}=2;y_{2}=1;\end{equation}
\begin{equation}3)\left\{\begin{matrix}
|x-y|=2,\\ |x+y|=2;
\end{matrix}\right.
\end{equation}
\begin{equation}x_{1}=-2; y_{1}=0;\end{equation}
\begin{equation}x_{2}=0;y_{2}=2;\end{equation}
\begin{equation}x_{3}=2; y_{3}=0;\end{equation}
\begin{equation}x_{4}=0;y_{4}=-2.\end{equation}
