Remember, if you multiply a negative number by a negative number, you will get a positive number, and positive numbers are greater than negative numbers. In this case, if I were to multiply each of these expressions with -1, I would get the following:
7(-1)+4=-3
-1-4=-5
5(-1)=-5
-5(-1)=5
And I'm sure you can imply how these values will correspond to other negative values. Basically, the last expression gives us a positive answer, which is larger than the others (which give a negative answer).
