Tricky algebra

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Tricky algebra

by dbodger » Wed Mar 25, 2009 11:18 am
I dont understand how to the get the answer to this problem even after reading the explanation. Its question from the quant OG.


If x does not = 2, then 3x^2(x-2)-x+2/ x-2 =







The correct answer is 3x^2-1.
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by tzvister » Wed Mar 25, 2009 5:16 pm
Just multiply the -x+2 part by (-1):
3x^2(x-2)+(-1)(x-2) / x-2

we get (3x^2-1)(x-2) / x-2

cancel nominator and denominator x-2
we get

3x^2-1

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by Brent@GMATPrepNow » Wed Mar 25, 2009 5:18 pm
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by dbodger » Thu Mar 26, 2009 8:50 am
thanks, that helps a lot.