Check for a spark and it fuel's getting through the line to the carb ok. If there's a spark and fuel in the line, then you've probably got a gummed up carb if the trimmer's sat there for some time. If you aren't sure what to do with the carb, its best to take it to a shop.
Ihave the same weedeater with spark,do i need a new coil
Dissconnect the kill wire from the coil, check the air gap in between the flywheel and coil,it should be .010"-.014" and make sure the flywheel magnet has enough magnetism to hold a good size screwdriver to it. If you still do not get spark then your coil is probably dead.
Is your plug fouling. If your plug is bone dry when you check it then you have a gummed carburator and no gas is getting to the cylinder. If you have a wet plug when you check it then I would look at buying a new coil. Also is your plug gapped properly? That can make a pretty big difference.