Gmat Prep Geom - Reposting

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Gmat Prep Geom - Reposting

by logitech » Mon Nov 24, 2008 6:57 pm
In the xy-plane, what is the y-intercept of line L?

(1) The slope of line L is 3 times its y-intercept?
(2) The x-intercept of line L is (-1/3)

OA E
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by jackcrystal » Mon Nov 24, 2008 11:06 pm
slope m = -(b/a) where b = y intercept and a = x intercept

I. slope is 3 times y-intercept,
3b = -b/a
a = -1/3 (basically it gives us x intercept value). can't find y-intercept with this value.

No Suff

II. x intercept = -1/3
we found this value before in I. this can't be used to find y intercept

Not Suff

I + II
3b = -b(-1/3)
=> 3b = 3b (Dahhh)


Therefore, (E)

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by logitech » Mon Nov 24, 2008 11:36 pm
Thanks jackcrystal!

y=slope X + b

and for some reason I thought the statement I as:

y = 3bx+b!!!

:(
LGTCH
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"DON'T LET ANYONE STEAL YOUR DREAM!"