Hei! :)
3x-7/2x+3 € Z
=> (2x+3) | (3x-7)
(2x+3) | -2(3x-7)
(2x+3) | (-6x+14) (1)
(2x+3) | 3(2x+3)
(2x+3) | (6x+9) (2)
=> (1) si (2) => (2x+3) | [(-6x+14)+(6x+9)]
(2x+3) | 23
=> (2x+3) | {-23, -1,1,23}
Cazul 1: 2x+3= -23 => x=-13
Cazul 2: 2x+3=-1 => x=-2
Cazul 3: 2x+3=1 => x= -1
Cazul 4: 2x+3=23 => x=10
=> x∈{-13, -2, -1, 10}