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# Absolute Values

Author Message
Intern
Joined: 12 Jun 2015
Posts: 7
Concentration: General Management
GMAT Date: 09-08-2015
GPA: 3.55
WE: Account Management (Manufacturing)

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20 Mar 2017, 08:18
hi Guys,

I wanted to know why in the attached screen shot the answer is x*2 = X*2

thanks
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Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 5866
GMAT 1: 760 Q51 V42
GPA: 3.82

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22 Mar 2017, 12:50
jamescarey86 wrote:
hi Guys,

I wanted to know why in the attached screen shot the answer is x*2 = X*2

thanks

$$\frac{x}{|y|} = -1$$ is equivalent to $$x = -|y|$$ or $$-x = |y|$$.
It is also equivalent to $$(-x)^2 = |y|^2 = y^2$$, and so we have $$x^2 = y^2$$.
Hence, D is the correct answer.

We have used a property as follows.
- $$|x| = a$$ is equivalent to $$x^2 = a^2$$.
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Re: Absolute Values &nbs [#permalink] 22 Mar 2017, 12:50
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