S + E(P) = (S+P) (F) + (S+B) (1-F)

-So I need to solve for F and what I mostly struggle with is the fact that multiple variables appear multiple times

- I am guessing you would subtract (S+P) and (S-B) from the left hand side first???

- Then, F+ (1-F) = F???

- Last combine like terms on the left hand side??

I am pretty sure I am doing it wrong, or at least I arrive at the wrong answer. All I am really interested in is what are the steps for solving a problem like this? Thanks.

Please feel free to include any articles/vids on the subject as well. Thanks.