Originally Posted by DukeSkywalker

Thats actually logic..
lets see if we can do it together..

p or q if then r on line 1. but i believe it becomes an and because its in bracktes, so p&q if then r for line 1

q or r if then it is not the case the s is x or t
p and s
therefore t.

shit man,, i forget which rule it is but you need to flip the first one around and change the cotraction to a conjunction to get the T by itself, then flip the entire second line but change the negative quantifier. then deduce and you should get your conclusion.
hope this helps
duke