\[\boxed{\text{556\ (556).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[|x| + |y| \leq 1;\]
\[1)\ x \geq 0,\]
\[y \geq 0 \Longrightarrow x + y \leq 1,\]
\[y \leq 1 - x;\]
\[2)\ x \leq 0,\]
\[y \geq 0 \Longrightarrow - x + y \leq 1,\]
\[y \leq 1 + x;\]
\[3)\ x \leq 0,\]
\[y \leq 0 \Longrightarrow - x - y \leq 1,\]
\[y \geq - x - 1;\]
\[4)\ x \geq 0,\]
\[y \leq 0 \Longrightarrow x - y \leq 1,\]
\[y \geq x - 1.\]