Is x > y ? (1) (x - y)(x - y) > 0 (2) y > 0

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Is x > y ?

(1) (x - y)(x - y) > 0
(2) y > 0

OFFICIAL ANSWER : E

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by GMATGuruNY » Fri Mar 31, 2017 2:40 am
ziyuenlau wrote:Is x > y ?

(1) (x - y)(x - y) > 0
(2) y > 0

Statement 1:

(x - y)² > 0.
This inequality is true for all values x and y such that x≠y.

Both statements are satisfied by x=2 and y=1 (in which case the answer to the question stem is YES) or by x=-2 and y=1 (in which case the answer to the question stem is NO).
Thus, the two statements combined are INSUFFICIENT.

The correct answer is E.
Last edited by GMATGuruNY on Fri Mar 31, 2017 10:19 pm, edited 1 time in total.
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by aji12 » Fri Mar 31, 2017 7:49 pm
Mitch
Ins't statement 1 - (x-y)^2?
GMATGuruNY wrote:
ziyuenlau wrote:Is x > y ?

(1) (x - y)(x - y) > 0
(2) y > 0
Statement 1:
x² - y² > 0
x² > y²

Both statements are satisfied by x=2 and y=1 (in which case the answer to the question stem is YES) or by x=-2 and y=1 (in which case the answer to the question stem is NO).
Thus, the two statements combined are INSUFFICIENT.

The correct answer is E.

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by GMATGuruNY » Fri Mar 31, 2017 10:20 pm
aji12 wrote:Mitch
Ins't statement 1 - (x-y)^2?
Good catch.
I've edited my response accordingly.
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