Đáp án: $(x,y)\in\{(4,-14),(10,-14),(2,2),(-4,2)\}$
Giải thích các bước giải:
$x^2-2=-xy+3y$
$\rightarrow x^2-9+7=-y(x-3)$
$\rightarrow (x-3)(x+3)+7=-y(x-3)$
$\rightarrow y=-(x+3)-\dfrac{7}{x-3}$
$\rightarrow 7\quad\vdots\quad x-3$
$\rightarrow x-3\in\{1,7,-1,-7\}$
$\rightarrow x\in\{4,10,2,-4\}$
$\rightarrow y\in\{-14,-14,2,2\}$
$\rightarrow (x,y)\in\{(4,-14),(10,-14),(2,2),(-4,2)\}$
