[mindless06795]

Hello,
I have a deck, currently 8ft off the group. It is attached to the house.
It extends about 5ft from the house, and is about 15th long. There are 2 concrete support columns on the front edge of the deck about 5 feet apart.
Basically I wanted to extend the deck out another 2 feet past these columns. My question is, will I have to add 2 more columns in the ground, or can I extend 2 feet without and issue? Also, if I can extend 2 feet without issue, how can I do that? Just extend the joists by attaching new joists to the side of old joists? Thank you.