absolute value

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Junior | Next Rank: 30 Posts
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absolute value

by jopup » Sun Jun 22, 2008 3:13 pm
Image

i dont understand how it is both sufficient

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by Nycgrl » Sun Jun 22, 2008 5:08 pm
1 statment says X^2 != 4
means X !=2 or -2

For |X+2|= 4....If X !=2 means its X= -6 ---suff

2nd statment X^2= 36 means X= 6 ---- suff

Hence C
!= not equal to

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by atlantic » Mon Jun 23, 2008 1:16 am
mod(x+2)=4 <-> x+2=4 or -x-2=4 <-> x=2 or x=-6

(1) says that x cannot be 2 or -2, so the answer is x=-6, SUFF

(2) says that x must be 6 or -6, so answer is x=-6, SUFF

Answer D