Tìm x, y ∈ Z biết: (x + 1)(y – 2) = 0

Bài toán 11: Tìm x, y Z biết. a) (x + 1)(y – 2) = 0
d) (x + 3)(y – 6) = -4
b) (x – 5)(y – 7) = 1
e) (x + 7)(5 – y) = -6
c) (x + 4)(y – 2) = 2
f) (12 – x)(6 – y) = -2