[tex] \frac{x-1}{3}= \frac{1}{y+1}=>(x-1)(y+1)=3. [/tex]
Cum x si y sunt intregi, distingem urmatoarele cazuri:
[tex]I. \left \{ {{x-1=1} \atop {y+1=3}} \right. \\ II. \left \{ {{x-1=-1} \atop {y+1=-3}} \right. \\ III. \left \{ {{x-1=3} \atop {y+1=1}} \right. \\ IV. \left \{ {{x-1=-3} \atop {y+1=-1}} \right. [/tex]
Solutiile sistemelor sunt urmatoarele:
I. (x,y)=(2,2)
II. (x,y)=(0,-4)
III. (x,y)=(4,0)
IV. (x,y)=(-2,-2)
Solutie: (x,y)∈{(-2,-2);(0,-4);(2,2);(4,0)}.
