Đáp án+giải thích các bước giải:
$(x-3)(y-3)=9$
TH1:
\(\left[ \begin{array}{l}x-3=3\\y-3=3\end{array} \right.\)
⇒ \(\left[ \begin{array}{l}x=6\\y=6\end{array} \right.\)
TH2:
\(\left[ \begin{array}{l}x-3=-3\\y-3=-3\end{array} \right.\)
⇒ \(\left[ \begin{array}{l}x=0\\y=0\end{array} \right.\)
TH3:
\(\left[ \begin{array}{l}x-3=1\\y-3=9\end{array} \right.\)
⇒ \(\left[ \begin{array}{l}x=4\\y=12\end{array} \right.\)
TH4:
\(\left[ \begin{array}{l}x-3=-1\\y-3=-9\end{array} \right.\)
⇒ \(\left[ \begin{array}{l}x=2\\y=-6\end{array} \right.\)
Vậy $x,y∈{(6;6);(0;0);(4;12);(2;-6)}$ thì $(x-3)(y-3)=9$
