How do I unlock my samsung android if I forgot my password ?

Turn off your tablet, then, once turn off, press volume up and power simultaneously, you will then come to recovery, once on recovery, select factory reset, or data/ wipe reset, it will reformat itself to factory default settings, but be reminded that it will erase all your downloaded application, photos that are stored in device memory, your contacts, if its backup and sync through gmail, you will recover them again, your photos if backed up to dropbox, you can also recover, your downloaded apps, try to log in to play store, check my apps, and you can download them again.

good luck.

You will have to wipe the phone back to factory settings using KIES on your computer