` (x - 5)(y + 3) = 6 ` `(x ; y) ∈ Z `
` => {(x - 5),(y + 3)} ∈ Ư(6) = {±1 ; ±2 ; ±3 ; ±6} `
Ta có bảng giá trị:
\begin{array}{|c|c|c|}\hline x-5&-6&-3&-2&-1&1&2&3&6\\\hline y+3&-1&-2&-3&-6&6&3&2&1\\\hline x&-1&2&3&4&6&7&8&11\\\hline y&-4&-5&-6&-9&3&0&-1&-2\\\hline\end{array}
Vậy ` (x;y) ∈ {(-1;-4),(2;-5),(3;-6),(4;-9),(6;3),(7;0),(8;-1),(11;-2)} `
