Does x = y?

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Does x = y?

by BTGmoderatorDC » Mon Nov 06, 2017 2:44 pm
Does x = y?

(1) x^2 - y^2 = 0
(2) (x - y)^2 = 0

What's the best way to determine whether statement 1 is sufficient?

OA B

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by Jay@ManhattanReview » Mon Nov 06, 2017 7:43 pm
lheiannie07 wrote:Does x = y?

(1) x^2 - y^2 = 0
(2) (x - y)^2 = 0

What's the best way to determine whether statement 1 is sufficient?

OA B
(1) x^2 - y^2 = 0

=> x^2 = y^2
=> x = ±y. x may nor may not be equal to y. Insufficient.

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

=> (x - y) = 0 => x = y. Sufficient.

The correct answer: B

Hope this helps!

-Jay
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