Value of X

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Value of X

by cartera » Thu Jan 22, 2009 6:50 am
(X^2+2x-8)/x^2-6x+8=?

A.1
B.-1
C.x/3
D.x+4/x-4
E.x+8-x-8



Im getting: (x+2)(x-4)/(x+5)(x+1)

How can I proceed

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by DanaJ » Thu Jan 22, 2009 6:52 am
You are getting it a bit wrong. The correct form would be:

(x+4)(x-2)/(x-4)(x-2), giving you (x+4)/(x-4)


Answer D.

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by gaggleofgirls » Thu Jan 22, 2009 7:51 am
Both your numerator and your denominator are a bit off:

Numerator = x^2 +2X -8, so you need (x - #) (X + #) where the #s are 2 apart, multiply to 8 and the larger # is + (so that you get +2x, not -2x). Those numbers are 2 and 4 such that the equation is (x - 2)(x + 4)

Denominator = x^2 - 6X + 8, so now you need (x - #)(x - #) (in order to get + # at the end) and you need numbers that are 2 apart and multiply to 8, so again you have 2 and 4 so that the equation is (x - 2) (x - 4)

(x - 2) (x + 4) / (x - 2)(x - 4) you can cancel out the (x-2) in both the numerator and the denominator and that leaves you with answer D.

-Carrie

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by krisraam » Thu Jan 22, 2009 8:03 am
IT IS D

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by aroon7 » Thu Jan 22, 2009 5:59 pm
yes it is D
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by johnybravo » Fri Jan 23, 2009 10:33 am
its D :)
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