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colakumarfanta
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My answer is Ccolakumarfanta wrote:Is x + y <0
1) x ^ 2-y ^ 2> 0
2) x-y <0
The statement alone is not sufficient because you don't know the sign of these variables
Try solving by both statement. first before solving try to paraphrase :
Statement 1) x^2 - y^2 > 0 equivalent to (x+1)(x-1) > 0, is it true only if both (x+1) and (x-1) are greater or less than 0
Since statement 2) tell us (x-y) < 0 therefore (x+1) is also < 0
Waiting for the official answer.
