im not sure if it s the same on your car, but on my teg and friends civic, its held in with one bolt.
if you are looking at the backseats from the front, it should look like this....
_______________________
_________________*____
______________________
the top horizonal line is the top of the back rest, the middle horizontal line is there people lose their change, the bottom line is the edge of the seat. the* is the nut.
hope that helps