Write the contrapositive of the major premise of this syllogism to determine whether the following argument is valid or invalid:
all nondogs are not blue.
jim is blue.
therefore, jim is a dog.

Its valid i think I'm not 100% sure tho 

its has to be , i really dont know lmaoo
invalid

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.