(1) x - y > -8runzun wrote:Is x>0
1)x-y>-8
2)x+y=8
If x = 2, y = 6 then x - y = 2 - 6 = -4 > -8, here x > 0.
If x = -2, y = 4, then x - y = -2 - 4 = -6 > -8, here x < 0.
From the above examples, it can be observed that x may or may not be > 0.
Therefore, statement 1 alone is NOT sufficient.
(2) x + y = 8
If x = 5, y = 3, then x + y =8; here x > 0.
If x = -2, y = 10, then x + y = 8; here x < 0.
Again from the above examples, it can be observed that x may or may not be > 0.
Therefore, statement 2 alone is NOT sufficient.
Now combine statements 1 and 2, x + y = 8 so that x - y > -8
Let us assume x to be any value < 0, say x = -1/4, and y = 33/4, then x + y = 8 and x - y = -17/2 or -8.5, which is < -8. From this it can be seen that if we take x < 0 then x - y < -8, which is a contradiction. This certainly means that x > 0.
The correct answer is C.
