how many different 5 player teams can be chosen from eight players? What formula do I use to solve this?

Answer 1

The number of combinations can be found from the formula
C(n,r)=n!/(r!(n-r)!)
n=total number of distinct objects
r=size of sample

For example,
there are 9 different fruits to choose from. The number of different samples of 6 fruits is equal to C(9,6)=9!/(6!(9-6)!)
=84

Answer 2

C(8,5)=8!/(5!(8-5)!) So do I * these numbers next to come up with the answer I got 120

Answer 3

Yes, basically that, but watch out for parentheses and order of operations.
Examples:
C(8,5)=8!/(5!(8-5)!)
=40320/(120*6)
=56
and
C(9,6)=9!/(6!(3!))
=362880/(720*6)
=84