-
heshamelaziry
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Question : is (x+y)^2 > x^2 + Y^2
This reduces to : is 2xy>0,or is xy>0
Statement 1:
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x+y < 0
Picking numbers we can see that both x and y can be -ve in which case xy>0
say,
x=-10,y=5 , x+y < 0 but xy <0
Hence,insufficient.
Statement 2:
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|x|=y
==> x=-y or x=y
If x=y,whether both are +ve or -ve,xy will be +ve
if x=-y,then xy will be -ve
Insufficient
Combining 1 and 2 we get
We need x+y < 0 hence if x=-y then x+y = 0 which violates statement1.
Hence X=y and hence xy>0
Pick C.
