y=(2x+4-9)/(x+2)
=[2(x+2)-9]/(x+2)
=2(x+2)/(x+2)-9/(x+2)
=2-9/(x+2)
9/(x+2)≠0
所以
2-9/(x+2)≠2
所以值域(-∞,2)∪(2,+∞)