All integer solutions of Diophantine equation 2 (x + y) = XY + 7 are______ ．

All integer solutions of Diophantine equation 2 (x + y) = XY + 7 are______ ．

(2x + 2x + 2Y + 2x + 2x + 2x + 2Y + 2y-4 = 3x (2-y) + 2 (Y-2) (2-y) = 3 (X-2) (2-2) (2-y) = 3 (X-2) when X-2 = 1, 2-y = 3 solution: x = 3: x = 3, y = 3: x = 3, y = 3 solution: x = 3, y = 3: x = 3, y = 1 (2) when X-2 = 3 = 2 = 3, 2-y = 1, 2-y = 1, 2-y = 1 solution: x = 5, and y = 1 (2) when X-2 = -2 = - 1, 2-2-2-y = - 2-2-2, 2-2-y = - 2-2-y = - 3, 2-2-y = - 3, 2-y = - 3 solution: x = 3 solution: x = 1: x = 1: x = 1: x = 1, y = 5, 1) (1, 5) （-1，3）