If the binary linear equation AX + by + 2 = 0 has two solutions, x = 2, y = 2, and x = 1, y = - 1, how much more can X and y equal

If the binary linear equation AX + by + 2 = 0 has two solutions, x = 2, y = 2, and x = 1, y = - 1, how much more can X and y equal

Substituting x = 1, y = - 1 into the equation, we get A-B + 2 = 0,
Substituting x = 2, y = 2 into the equation, we get 2A + 2B + 2 = 0
a=-3/2 ,b=1/2 .
∴-3x/2+y/2+2=0.
This is an indefinite equation, solving endless worries
For example: x = 0, y = - 4; X = 4 / 3, y = 0 and so on