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Harish Dorai
 
 

Which of the following inequalities has a solution set, when

by Harish Dorai Mon Jul 30, 2007 3:54 pm

Which of the following inequalities has a solution set, when graphed on the number line, is a single line segment of finite length?

A) x^4 >= 1
B) x^3 >= 27
C) x^2 >= 16
D) 2 <= |x| <= 5
E) 2 <= 3x+4 <= 6

Can some one give me an explanation? I don't think (A), (B) and (C) are the solutions as they will represent non-linear graphs. It has to be either (D) or (E).
givemeanid
 
 

by givemeanid Mon Jul 30, 2007 5:08 pm

You are right about A, B and C.

(D) 2 <= |x| <= 5
|x| >= 2
x >= 2 or x <= -2
x <= 5 or x >= -5

These are two segments. One is from -5 to -2. The other from 2 to 5.

(E) 2 <= 3x+4 <= 6
-2 <= 3x <= 2
-2/3 <= x <= 2/3

This is one continuous segment.
cindyqtran
 
 

by cindyqtran Mon Jul 30, 2007 6:36 pm

I agree with givemeanid, the answer is E

answer D is not a "single line segment" but 2 segments.
StaceyKoprince
ManhattanGMAT Staff
 
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by StaceyKoprince Tue Jul 31, 2007 1:19 am

Great job, guys!
Stacey Koprince
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