The question states: Is xy > x + y?Taniuca wrote:Someone help me out to find out, the easiest and best way to approach the following problem, to get the right answer.
Is the product of x and y greater than the sum of x and y?
(1) xy < 0
(2) x > -y
(1) xy < 0 implies that either x should be positive and y negative or x should be negative and y positive.
If x = -2 and y = 5, then xy = -10 and x + y = 3. Here xy < x + y
If x = -4 and y = 2 then xy = -8 and x + y = -2. Here also xy < x + y
If x = 1/2 and y = -1 then xy = -1/2 and x + y = -1/2. Here xy = x + y
So, we don't get a unique answer. Hence (1) is NOT SUFFICIENT to answer the question.
(2) x > -y implies x + y > 0.
If x = 8, y = -2, xy = -16 and x + y = 6. so, xy < x + y
If x = 3 and y = 2 then xy = 6 and x + y = 5. Here, xy > x + y
No unique answer. So, (2) is NOT SUFFICIENT.
Combining (1) and (2), we know that one of x and y is negative such that x + y > 0. So, the product xy is negative and x + y is positive implies that xy < x + y
The correct answer is (C).
Hope this helps?
