Question 9358: Having problem helping daughter with homework,
thank you very much Found 2 solutions by longjonsilver, JimMarshall:Answer by longjonsilver(2297) (Show Source):
You can put this solution on YOUR website! when you have 2 symbols together like here, , there are rules that help to simplify. I have written a Lesson on this website that explains these very simple rules (but to be honest, rather difficult to explain why, in a meaningful way).
Anyway - and - can be thought of as + so we get which in turn is 77x