Question

Giải hệ phương trình

\(\left\{{}\begin{matrix}x-y=2\\3x+2y=11\end{matrix}\right.\)

Answer 1

\(\left\{{}\begin{matrix}x-y=2\\3x+2y=11\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}2x-2y=4\\3x+2y=11\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}5x=15\\x-y=2\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}x=3\\3-y=2\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}x=3\\y=1\end{matrix}\right.\)

Vậy hệ phương trình có tập nghiệm là: \(\left\{{}\begin{matrix}x=3\\y=1\end{matrix}\right.\)

Answer 2

\(\left\{{}\begin{matrix}x-y=2\\3x+2y=11\end{matrix}\right.\)\(\Leftrightarrow\left\{{}\begin{matrix}5y=5\\5x=15\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}y=1\\x=3\end{matrix}\right.\)