If the points m (a + 1,2), n (3, b-2) and Mn are parallel to the y-axis, find ab The satisfying conditions of ab

If the points m (a + 1,2), n (3, b-2) and Mn are parallel to the y-axis, find ab The satisfying conditions of ab

If Mn is parallel to the y-axis, then the distances from the points m and N to the y-axis are equal, and the abscissa of M and N is small, i.e. a + 1 = 3, then a = 2
Point n can be any point on the line Mn except point m, so B-2 is not equal to 2, so B is equal to 4