if x > 0...

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if x > 0...

by ashkonj » Sun Dec 06, 2009 7:50 pm
If x>0, which of the following best approximates the value of x if 5^23-4^11=x^2?

5^34
5^12
5^10
5^5
5^3

OA 5^12

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by djkvakin » Mon Dec 07, 2009 2:32 pm
The OA seems odd because if the solution is 5^12, then x^2=5^24. So our equation is 5^23-4^11 should be less than 5^23, and instead, it's more. Did you type the question correctly?