Click here to skip this discussion and go straight to the assignment. This is a pair if modus ponens arguments, linked by the fact that you don't know which of the antecedents is true, so you don't know which of the consequents is. This one is simple.
Simplification is like a freebie.
You should always begin with simplification if you have it. You can then break it apart into separate parts. As with DS, though, by convention, we only get to derive the left conjunct by this rule, to get the right one we will use a rule we will learn in the next lesson. This one is often the one to use if it looks like you can't do anything. Don't get the names of conjunction and addition confused.