Question

\(\left\{{}\begin{matrix}x-y=3\\3x-4y=2\end{matrix}\right.\)

Answer 1

\(\left\{{}\begin{matrix}x-y=3\\3x-4y=2\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}3x-3y=9\\3x-4y=2\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x-y=3\\y=7\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x-7=3\\y=7\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=10\\y=7\end{matrix}\right.\)

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Answer 2

\(\left\{{}\begin{matrix}x-y=3\\3x-4y=2\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}3x-3y=9\\3x-4y=2\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}y=7\\x=10\end{matrix}\right.\)