xy + 2x + y = 3
=> \(x\left(y+2\right)+\left(y+2\right)=5\)
\(\Rightarrow\left(x+1\right)\left(y+2\right)=5\)
| x+1 | 1 | 5 | -1 | -5 |
| y+2 | 5 | 1 | -5 | -1 |
| x | 0 | 4 | -2 | -6 |
| y | 3 | -1 | -7 | -3 |
Vậy:.......
Ta có : xy+2x+y=3
=> x(y+2)+y+2-2=3
=> x(y+2)+(y+2)=5
=>(x+1)(y+2)=5
Vậy (x;y)=(0;3);(4;-1);(-2;-7);(-6;-3)