7.1 surround sound placement?

Question

can you put 7.1 surround back speakers on the side walls like the surround speakers are

Answer 1

You can but you will lose the sound effect from behind you. In essence you would make it like 5.1 surround sound.  If the original soundtrack has 7.1 you will lose 2 speakers in that placement. Someone coming from behind will sound as if they are coming from the right or left sides, inside your head or slightly above you.

Answer 2

Yes.