Question

\(\left\{{}\begin{matrix}x+\sqrt{y}=5\\2x-\sqrt{y}=7\end{matrix}\right.\)

Answer 1

\(\left\{{}\begin{matrix}x+\sqrt{y}=5\\2x-\sqrt{y}=7\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}3x=12\\\sqrt{y}=5-x\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}x=4\\y=1\end{matrix}\right.\)

Vậy hệ phương trình có nghiệm \(\left(x;y\right):\left(4;1\right)\)