Keep in mind that "simplify" doesn't always mean "make it simpler looking".
-(6-4) = -2 -- That is both simplified and simpler looking.
1/sqrt(2) = sqrt(2)/2 -- Looks about the same, but MANY teachers and texts consider it "simplified".
11/2 = 5½ -- I think this one went the wrong direction. This "simplification" actually made it look worse and made it less useful.
It's sort of a judgment call, sometimes.