Integers

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Integers

by moneyman » Sun Nov 23, 2008 9:23 am
Why is it not D?

Sq.rt[(x-3)^2] = (3-x)

Squaring both sides, we get (x-3)^2 = (3-x)^2 and if you use any value the equation is satisfied right?

What am I missing here?
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Maxx

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by Tryingmybest » Sun Nov 23, 2008 10:00 am
What if X is a negative number? Then A will fail



The Stem is if X is negative or not? It is answered by B

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by moneyman » Tue Nov 25, 2008 1:35 am
Sq.rt[(x-3)^2] = (3-x)

Squaring both sides, we get (x-3)^2 = (3-x)^2 -->(1)

Put x=-2 in (1) and we get (-5)^2=(5)^2

SO why not A ? Guys pls help me on this one
Maxx

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by bluementor » Tue Nov 25, 2008 3:23 am
In statement 1, all we know about x is that its not equal to 3.

If x < 3, say x = 2, then you question stem will yield YES.
If x>3, say x = 4, then your question stem will yield NO.

Insufficient.

the sqrt() function will only yield a positive value.

Post back if further explanation is needed. And good luck for your exam tmrw!

-BM-