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Inequality Help!

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Inequality Help!

by heshamelaziry » Thu Oct 15, 2009 8:00 pm
If x and y are integers and xy ≠ 0, is x - y > 0 ?

(1) x /y < 1/2

(2) Sqrtx^2= x and Sqrty^2= y


In statement 2. How come the answer states that from statement 2 we know that each x and y is positive !!!!? :x each will be X^2 = x^2 and y^2 = y^2 only means that x=x and y=y but does not say positive or negative.
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by sanjana » Thu Oct 15, 2009 9:42 pm
u cant find the sqrt of a negative number.
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by heshamelaziry » Thu Oct 15, 2009 10:03 pm
sanjana wrote:u cant find the sqrt of a negative number.
I didn't take the square root of x^2, I divided each side by x to simplify and got x = x !!!!


I guess i am terrible with inequalities.
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by crackgmat007 » Fri Oct 16, 2009 2:04 pm
heshamelaziry wrote:
sanjana wrote:u cant find the sqrt of a negative number.
I didn't take the square root of x^2, I divided each side by x to simplify and got x = x !!!!


I guess i am terrible with inequalities.
Here is a simple rule

Sqrtx^2 = x means |x| = x

Is the answer C?
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by heshamelaziry » Fri Oct 16, 2009 5:47 pm
crackgmat007 wrote:
heshamelaziry wrote:
sanjana wrote:u cant find the sqrt of a negative number.
I didn't take the square root of x^2, I divided each side by x to simplify and got x = x !!!!


I guess i am terrible with inequalities.
Here is a simple rule

Sqrtx^2 = x means |x| = x

Is the answer C?
OA is B
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by crackgmat007 » Fri Oct 16, 2009 6:34 pm
Stmt 2 tells that both x & y are positive & question stem states that x & y are not equal to 0 and that x & y are integers. Picking numbers (x = 3, y = 4 & x = 3, y = 2) proves that B is insufficient.

If you have the official explanation, pls post.
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by heshamelaziry » Fri Oct 16, 2009 7:45 pm
Apologize. OA is C
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