To combine like terms, you have to add the same variables and all
First You have to find if the Numbers are positive or Negative
2s is positive
4w is Negative because i has Minus sigh before it
5 is Positive because it has added sigh
6s s Positive because it has added sign
Second you have to find the Like terms
2s+6s=8s
so, the new equation is
8s-4w+5.
That is the simplest
If you have questions just ask me I went through it pretty fast