If x^2 - 1 = 2, then |x| =

Question

A. 0
B. 0.5
C.  \sqrt{2} 
D. 1.5
E.  \sqrt{3}

pushpitkc · Answer

Since  x^2  - 1 = 2
 x^2 = 3
x =  \sqrt{3} (Option E)

BrentGMATPrepNow · Answer

Given: x² - 1 = 2
Add 1 to both sides: x² = 3
So, EITHER x =  √3  OR x =  -√3

We have two possible values for x, HOWEVER, the question asks for the value of |x|

| √3 | = √3 AND | -√3 | = √3
Answer:  E

Cheers,
Brent

Abhishek009 · Answer

x^2 - 1 = 2

Or,  x^2 = 3

So,  x = \sqrt{3}

Hence, answer will be (E)

Milinsdesai · Answer

x^2−1=2

Hence, X^2 = 3

So Mode of X Must be = √3.

Answer is E.

JeffTargetTestPrep · Answer

We can simplify the given equation:
 
x^2 - 1 = 2
 
x^2 = 3
 
√x^2 = √3
 
|x| = √3
 
Answer: E

ydmuley · Answer

x^2 - 1 = 2

X^2 = 3

x = \sqrt{3}  OR  x = -\sqrt{3}

|x| = \sqrt{3}

\sqrt{3}

Answer is E

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If x^2 - 1 = 2, then |x| =

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