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GMAT, GRE Quant: Absolute Value Problem

 Which of the following represents all the possible values of x that are solutions to the equation 3x=|x^2 -10|?


A. -5, -2, and 0
B. -5, -2 , 2, and 5
C. -5 and 2
D. -2 and 5
E. 2 and 5



x>3.33

Positive:

3x=x^2-10
-x^2+3x+10=0
x^2-3x-10=0
(x-5)*(x+2)=0
x=5, x=-2
x=5 falls in the range of x>3.33. 
X=2 does not.

x<3.33

Negative:

3x=-(x^2-10)
3x=-x^2+10
x^2+3x-10=0
(x+5)*(x-2)=0
x=-5, x=2
Both -5 and 2 falls within the range of x<3.33

Solutions = -5,2,5




Jeremiah LaBrash

Jeremiah LaBrash is a programmer and CIO for a CCaaS telecom company based in New York, NY. If you have math or verbal questions you’re having difficulty with and would like Jeremiah LaBrash to solve them and parse them into understandable parts, please leave a comment below or mail jr@thelevel11.com  


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