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Hi mukherjee.tanuj3,
This question can be solved with TESTing Values...
We're asked if one calculation is equal to another. This is a YES/NO question.
Fact 1: X cannot = 3
If X = 4, root(1) does NOT equal (3-4) and the answer to the question is NO
If X = 2, root(1) does equal (3-2) and the answer to the question is YES
Fact 1 is INSUFFICIENT
Fact 2: -X|X| > 0
This tells us that X MUST be negative
If X = -1, root(16) does equal (3 - (-1)) and the answer to the question is YES
If X = -2, root(25) does equal (3 - (-2)) and the answer to the question is YES
If X = -3, root(36) does equal (3 - (-3)) and the answer to the question is YES
The answer remains the same as long as X is negative.
Fact 2 is SUFFICIENT
Final Answer: B
GMAT assassins aren't born, they're made,
Rich
This question can be solved with TESTing Values...
We're asked if one calculation is equal to another. This is a YES/NO question.
Fact 1: X cannot = 3
If X = 4, root(1) does NOT equal (3-4) and the answer to the question is NO
If X = 2, root(1) does equal (3-2) and the answer to the question is YES
Fact 1 is INSUFFICIENT
Fact 2: -X|X| > 0
This tells us that X MUST be negative
If X = -1, root(16) does equal (3 - (-1)) and the answer to the question is YES
If X = -2, root(25) does equal (3 - (-2)) and the answer to the question is YES
If X = -3, root(36) does equal (3 - (-3)) and the answer to the question is YES
The answer remains the same as long as X is negative.
Fact 2 is SUFFICIENT
Final Answer: B
GMAT assassins aren't born, they're made,
Rich
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√(x - 3)^2 = 3 - x is possible only if x ≤ 3, in order to have a non-negative square root. So the question changes to:[email protected] wrote:
Is x ≤ 3?
(1) x ≠3 doesn't ensure x < 3, hence insufficient.
(2) This statement suggests that x < 0, because ×€x×€ cannot be negative. Hence, x is always less than 3. [spoiler]Sufficient
Take B[/spoiler]
The mind is everything. What you think you become. -Lord Buddha
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
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Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
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Be definition:Is sqrt [(x-3)^2] = 3-x
1) x is not equal to 3
2) -x*|x| > 0
√(x²) = |x|.
|x-y| is the DISTANCE between x and y.
Question rephrased: Is |x-3| = 3-x?
In other words:
Is the DISTANCE between x and 3 equal to the DIFFERENCE between 3 and x?
A DIFFERENCE can be negative, 0, or positive.
A DISTANCE must be greater than or equal to 0.
For the DIFFERENCE between two values to be equal to the DISTANCE between the two values, the DIFFERENCE -- like the DISTANCE -- must be greater than or equal to 0:
3-x≥0
x≤3.
Thus, |x-3| = 3-x as long as x is not greater than 3.
Question stem, rephrased: Is it true that x is not greater than 3?
Statement 1: x is not equal to 3.
It is possible that x<3 or that x>3.
INSUFFICIENT.
Statement 2: -x*|x| > 0 .
Thus, the left-hand side must be (+)(+) or (-)(-).
Since |x| cannot be negative, both factors on the left-hand side must be positive.
Thus:
-x>0
x<0.
Since x<0, we know that x is not greater than 3.
SUFFICIENT.
The correct answer is B.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
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Student Review #3