\[ \left\{\begin{matrix}9x-2y=-17;\\x-2y=7\end{matrix}\right.
\left|\begin{matrix}\;\\\;\times(-1)\end{matrix}\right.
\left\{\begin{matrix}9x-2y=-17;\\-x+2y=-7\end{matrix}\right.
\left|\begin{matrix}I+II\\\;\end{matrix}\right.
\left\{\begin{matrix}8x=-24;\\x-2y=7\end{matrix}\right. \]\[
\left\{\begin{matrix}x=-3;\\2y=x-7\end{matrix}\right.
\left\{\begin{matrix}x=-3;\\2y=-3-7\end{matrix}\right.
\left\{\begin{matrix}x=-3;\\y=-5\end{matrix}\right. \]
\[ \left\{\begin{matrix}5x-2y=15;\\2x-y=7\end{matrix}\right.
\left|\begin{matrix}\;\\\;\times(-2)\end{matrix}\right.
\left\{\begin{matrix}5x-2y=15;\\-4x+2y=-14\end{matrix}\right.
\left|\begin{matrix}I+II\\\;\end{matrix}\right. \]\[ \left\{\begin{matrix}x=1;\\2x-y=7\end{matrix}\right.
\left\{\begin{matrix}x=1;\\y=2x-7\end{matrix}\right.
\left\{\begin{matrix}x=1;\\y=-5\end{matrix}\right. \]
аккаунтом
