gmatblood wrote:If x and y are integers such that x < y < 0, what is x - y?
(1) (x + y)(x - y) = 5
(2) xy = 6
Statement 1: (x + y)(x - y) = 5.
To yield a product of 5, only two combinations of factors are possible: 5 and 1, -5 and -1.
Since x and y are both negative integers, the factors needed here are -5 and -1.
Since it's not possible that x+y = -1 (the sum of two negative integers cannot be -1), we know that x+y = -5 and that x-y = -1.
SUFFICIENT.
Statement 2: xy=6.
If x=-6 and y=-1, then x-y = -6-(-1) = -5.
If x=-3 and y=-2, then x-y = -3-(-2) = -1.
INSUFFICIENT.
The correct answer is
A.
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