Is y>0?

(1) x^2−y^2=0

(2) x^2+y^2=0

statement 1 x^2−y^2=0

x^2−y^2 => ( x+y ) ( x-y ) = 0

x+y = 0 and x-y = 0

x = -y and x = y ( no information about x and y )

Insuff.statement 2x^2+y^2=0

Now, one thing we know from here that x^2 will always be positive and y^2 will always be positive

So, Sum of two positives can only be zero if both of them are zero.

Hence sufficient .

y = 0Regards

SandySilva

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Regards

SandySilva

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Hit kudos if my post helped (: