\[\boxed{\text{674.}\text{\ }\text{еуроки}\text{-}\text{ответы}\text{\ }\text{на}\text{\ }\text{пятёрку}}\]
\[2x - y = 4\]
\[y = 2x - 4\]
\[график\ \text{b.}\]
\[x - y = - 2\]
\[y = x + 2\]
\[график\ a.\]
\[y + 4 = 0\]
\[y = - 4\]
\[график\ d.\]
\[x - 6 = 0\]
\[x = 6\]
\[график\ c.\]