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nicole
11-05-2013, 06:29 AM
Which of the following is true given that |x+4|>5?

(A) x>1

(B) -9<x<1

(C) x<-9 \ or \ x>1

(D) x>1 \ or \ x<-9

(E) 1<x<9

Thanks!;)

Brynlee
11-05-2013, 06:30 AM
The inequality |x|>a \ where \ a>0 is equivalent to x<-a \ or \ x>a.

In our case the inequality |x+4|>5 is equivalent to x+4<-5 \ or \ x+4>5

|x+4|>5 \Rightarrow x+4<-5 \ or \ x+4>5 \Rightarrow

x<-9 \ or \ x>1

Therefore the correct answer is (D).

nicole
11-05-2013, 06:33 AM
Thanks Brynlee!!