Question

Answer 1

Answer 2

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

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

<=> \(\left\{{}\begin{matrix}x=3+y\\9+3y-4y=2\end{matrix}\right.\)

<=> \(\left\{{}\begin{matrix}x=3+y\\9-y=2\end{matrix}\right.\)

<=>\(\left\{{}\begin{matrix}x=3+y\\y=7\end{matrix}\right.\)

<=>\(\left\{{}\begin{matrix}x=10\\y=7\end{matrix}\right.\)

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