Question

determinati perechile de numere intregi (x, y) pt care : xy+x-2y=7 ma ajutati va rog frumos ?????????

Answer 1

x(y+1)-2y-2=5
x(y+1)-2(y+1)=5
(x-2)(y+1)=5
5=1*5=5*1=(-1)*(-5)=(-5)*(-1)
x-2=1 , x=3;y+1=5,y=4
x-2=5,x=7;y+1=1,y=0
x-2=-1,x=1; y+1=-5, y=-6
x-2=-5, x=-3; y+1=-1, y=-2