Is x > y ?
(1) -4x + 2y < y - 3x
(2) wx > wy
In statement 2, why can't I divide each side by w and get x > y ??????????????
Inequality Madness
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Last edited by heshamelaziry on Thu Oct 15, 2009 10:06 pm, edited 1 time in total.
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Statement 1
-----------
2y-y < -3x+4x
y<x - sufficient.
Statement 2
------------
wx-wy > 0
w(x-y) > 0
Now either W>0 and X-Y > 0 ==> X>Y
or W<0 and X-Y < 0 ==> X<Y
Hence the answer could be yes or no.
Insufficient.
IMO : A
Whats the OA?
-----------
2y-y < -3x+4x
y<x - sufficient.
Statement 2
------------
wx-wy > 0
w(x-y) > 0
Now either W>0 and X-Y > 0 ==> X>Y
or W<0 and X-Y < 0 ==> X<Y
Hence the answer could be yes or no.
Insufficient.
IMO : A
Whats the OA?
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sanjana wrote:Statement 1
-----------
2y-y < -3x+4x
y<x - sufficient.
Statement 2
------------
wx-wy > 0
w(x-y) > 0
Now either W>0 and X-Y > 0 ==> X>Y
or W<0 and X-Y < 0 ==> X<Y
Hence the answer could be yes or no.
Insufficient.
IMO : A
Whats the OA?[/quot
In statement 2, why can't I divide each side by w and get x > y ??????????????
OA is A. how you figure to do it this way rather than what I am describing above that is correct too !!!!!!!!!!!!!!
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In Inequalities you should never divide by a number unless you know the sign of the number.
Also Suppose you have a normal equation
say,
X^2-X = 0
if you divide by x you get,
x-1=0,hence x=1
By doing this you have missed one solution of the equation completely,i.e x=0
You should always do,
x(x-1)=0
hence,x=0 or x=1.
Hope this helps!
Also Suppose you have a normal equation
say,
X^2-X = 0
if you divide by x you get,
x-1=0,hence x=1
By doing this you have missed one solution of the equation completely,i.e x=0
You should always do,
x(x-1)=0
hence,x=0 or x=1.
Hope this helps!