\(2xy-10x-5y=-15\)
\(\Rightarrow2xy-10x-5y+15=0\)
\(\Rightarrow2xy-10x-5y+25=10\)
\(\Rightarrow2x\left(y-5\right)-5\left(y-5\right)=10\)
\(\Rightarrow\left(2x-5\right)\left(y-5\right)=10\)
\(\Rightarrow2x-5;y-5\inƯ\left(10\right)\)
\(Ư\left(10\right)=\left\{\pm1;\pm2;\pm5;\pm10\right\}\)
Mà \(2x-5\) lẻ nên:
\(\left[{}\begin{matrix}\left\{{}\begin{matrix}2x-5=1\Rightarrow2x=6\Rightarrow x=3\\y-5=10\Rightarrow y=15\end{matrix}\right.\\\left\{{}\begin{matrix}2x-5=-1\Rightarrow2x=4\Rightarrow x=2\\y-5=-10\Rightarrow y=-5\end{matrix}\right.\\\left\{{}\begin{matrix}2x-5=5\Rightarrow2x=10\Rightarrow x=5\\y-5=2\Rightarrow y=7\end{matrix}\right.\\\left\{{}\begin{matrix}2x-5=-5\Rightarrow2x=0\Rightarrow x=0\\y-5=-2\Rightarrow y=3\end{matrix}\right.\end{matrix}\right.\)
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