Tìm x, y : (x-1).(y-7)=7 MN ơi cứu mk bài nỳ zới !!

`(x-1).(y-7)=7`

`=>x-1, y-7 \in Ư_((7))`

Ta có bảng:

\begin{array}{|c|c|c|}\hline \text{x-1}&\text{y-7}&\text{x}&\text{y}\\\hline \text{-1}&\text{-7}&\text{0}&\text{0}\\\hline \text{-7}&\text{-1}&\text{-6}&\text{6}\\\hline \text{1}&\text{7}&\text{2}&\text{14}\\\hline \text{7}&\text{1}&\text{8}&\text{8}\\\hline\end{array}

Vậy `(x,y)\in{(0,0);(-6,6);(2,14);(8,8)}`.