If x and y are integers, is xy even?
1.) x = y + 1
2.) x/y is an even integer
The solution says D, that each statement alone is sufficient. Why is this the case and not B, that only 2. is sufficient?
I understand that with consecutive integers (x = y + 1), that one must be odd and one must be even, but doesn't this only hold true if both integers cannot equal 0? In this case, consider y = -1. Then x = 0 and xy = 0, and therefore 1.) should be insufficient.
1.) x = y + 1
2.) x/y is an even integer
The solution says D, that each statement alone is sufficient. Why is this the case and not B, that only 2. is sufficient?
I understand that with consecutive integers (x = y + 1), that one must be odd and one must be even, but doesn't this only hold true if both integers cannot equal 0? In this case, consider y = -1. Then x = 0 and xy = 0, and therefore 1.) should be insufficient.
