If x<0 then root (-x/x/) = ?
A. -x
B. -1
C.1
D.x
E. root X
IMO: D but not
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GMATprep2: if x<0
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truplayer256
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The best way to solve this problem would be by plugging in. Since x has to be less than 0, let's say x is -4.
sqrt(-(-4)*|-4|)=sqrt(4*4)=sqrt(16)=4
See what answer choice matches this option. Remember that x=-4
A.) -(-4)=4 Looks good. Let's try the other answer choices to make sure that there aren't any other choices similar to this one.
B.) -1. No.
C.) 1. This would have only been true if you had picked x to be -1. No
D.) x, x=-4. No
E.) root(x). root(-4). That's impossible without imaginary numbers. No.
It looks like A is our answer.
sqrt(-(-4)*|-4|)=sqrt(4*4)=sqrt(16)=4
See what answer choice matches this option. Remember that x=-4
A.) -(-4)=4 Looks good. Let's try the other answer choices to make sure that there aren't any other choices similar to this one.
B.) -1. No.
C.) 1. This would have only been true if you had picked x to be -1. No
D.) x, x=-4. No
E.) root(x). root(-4). That's impossible without imaginary numbers. No.
It looks like A is our answer.
