Question

(x-1)(y+2)= -5
va rog frum.

Answer 1

 rezolvam in ZxZ ; in RxR exista o infinitate de solutii

  (x-1)(y+2)=-5= -1*5=1*(-5)
 deci sau
x-1=-1  si
y+2=5 
adica x=-0 si y=3

sau x-1=5
       y+2=-1
adica x=6;y=-3


sau

x-1=1
y+2=-5
adica x=2 si y=-7

sau
 x-1=-5
y+2=1

adica
x=-4; y=-1


deci (x;y) ∈{ (0;3);(6;-3) (2;-7) ; (-4;-1)}