What is the value of |x| ?
(1) x = - |x|
(2) x^2 = 4
OA: B
Please help, Experts, what's the best approach to solving this problem. Thanks!
OG2015 DS What is the value
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- lionsshare
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Statement 1: x = -|x|lionsshare wrote:What is the value of |x| ?
(1) x = - |x|
(2) x^2 = 4
OA: B
Please help, Experts, what's the best approach to solving this problem. Thanks!
Since |x| is positive, we can deduce that x is a negative number; however, the value of x, thus |x| is interminable. Insufficient.
Statement 2: x^2 = 4
=> x = ±2
=> |x| = |±2| = 2. Sufficient.
The correct answer: B
Hope this helps!
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We need to determine the absolute value of x.lionsshare wrote:What is the value of |x| ?
(1) x = - |x|
(2) x^2 = 4
Statement One Alone:
x = -|x|
If x = -|x|, then x must be negative or 0. For example, if x = -3, -3 = -|-3|. However, since we do not have an exact value for x, statement one is not sufficient. We can eliminate answer choices A and D.
Statement Two Alone:
x^2 = 4
We can simplify by taking the square root of both sides of the equation:
√x^2 = √4
|x| = 2
Since we have 2 as the value for |x|, this answers the question.
Answer: B
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