What is the value of y?
(1) 3|x2 - 4| = y - 2
(2) |3 - y| = 11
It's From MGMAT CAT and Answer is C
What is the value of y?
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- amirhakimi
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Sincerely,
Amir,
The only place that "Success" comes before "Trying" is in the dictionary!
Amir,
The only place that "Success" comes before "Trying" is in the dictionary!
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- Brent@GMATPrepNow
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amirhakimi wrote:What is the value of y?
(1) 3|x² - 4| = y - 2
(2) |3 - y| = 11
Target question: What is the value of y?
Statement 1: 3|x² - 4| = y - 2
Tons of possible values for y. Here are two cases:
Case a: x = 0, in which case y = 14
Case b: x = 1, in which case y = 11
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: |3 - y| = 11
If |something| = k (where k > 0), then something = k, or something = -k
So, we get two possible equations:
3 - y = 11, in which case y = -8
3 - y = -11, in which case y = 14
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined
Statement 2 tells us that y equals EITHER -8 OR 14
Statement 1 tells us that 3|x² - 4| = y - 2
Since absolute values are always greater than or equal to 0, we know that y - 2 > 0
This means that y >2
If y >2, then we can rule out the possibility that y = -8, which means y MUST equal 14
Since we can answer the target question with certainty, the combined statements are SUFFICIENT
Answer = C
Cheers,
Brent
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Hi Brent ,
Statement 1: 3|x² - 4| = y - 2
Can we solve the statement 1 by changing the sign like below.
3x^2-12=y-2
3x^2-y=10 .......(|)
and
3x^2-12=-y+2
3x^2+y=14..........(||)
Please suggest and correct me if i am wrong.
Thanks
Shreyans
Statement 1: 3|x² - 4| = y - 2
Can we solve the statement 1 by changing the sign like below.
3x^2-12=y-2
3x^2-y=10 .......(|)
and
3x^2-12=-y+2
3x^2+y=14..........(||)
Please suggest and correct me if i am wrong.
Thanks
Shreyans