what is the value of x?

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what is the value of x?

by alexandrabiorka » Thu Aug 14, 2014 8:38 am
If y = -z, where z is a prime number, what is the value of x?

1.) |x+2| + 2 = y

2.) y > -8

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by Brent@GMATPrepNow » Thu Aug 14, 2014 8:49 am
alexandrabiorka wrote:If y = -z, where z is a prime number, what is the value of x?

1.) |x+2| + 2 = y

2.) y > -8
Are you sure you transcribed the question correctly?

There's a problem with statement 1.
|x + 2| is greater than or equal to zero (that's the nature of absolute values)
So, |x + 2| + 2 is greater than or equal to 2
In other words, |x + 2| + 2 is POSITIVE
If y = |x + 2| + 2, then y is POSITIVE

HOWEVER, we're told that y = -z, where z is a prime number
Since all primes are positive, this means that z is positive.
Since y = -z, we can conclude that y is NEGATIVE

Obviously y cannot be both positive and negative.

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Brent
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by GMATinsight » Thu Aug 14, 2014 8:53 am
alexandrabiorka wrote:If y = -z, where z is a prime number, what is the value of x?

1.) |x+2| + 2 = y

2.) y > -8
Question : what is the value of x?

Given : y = -z, where z is a prime number i.e. y = -2 or -3 or -5 etc...

Statement 1) |x+2| + 2 = y

But |x+2| + 2 Must be positive

and as per question y must be negative Integer as Z is a Prime Number and y = -z

This seems Incorrect set of information...

Please check if the information is appropriate...
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