(1)∵h=2.6,球从O点正上方2m的A处发出,∴抛物线y=a(x-6)2+h过点(0,2),∴2=a(0-6)2+2.6,解得:a=- 1 60 ,故y与x的关系式为:y=- 1 60 (x-6)2+2.6,(2)当x=9时,y=- 1 60 (x-6)2+2.6=2.45>2.43,所以球能过球网;当y=0时,- 1 60 (x-6)2+2.6=0,解得:x1=6+2 39 >18,x2=6-2 39 (舍去)故会出界.