y in the system above?

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y in the system above?

by sanju09 » Wed Nov 16, 2011 3:48 am
x + 2 y + 3 z = 2

x + y - z = 0

2 x + 2 y - z = 0

What is the value of y in the system above?
(A) -2
(B) -1
(C) 0
(D) 1
(E) 2
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by user123321 » Wed Nov 16, 2011 4:01 am
sanju09 wrote:x + 2 y + 3 z = 2

x + y - z = 0

2 x + 2 y - z = 0

What is the value of y in the system above?
(A) -2
(B) -1
(C) 0
(D) 1
(E) 2
from 2nd and 3rd equation, z = 0
subtract 2nd from 1st, which gives y = 2

IMO E
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Want to do it right the first time.

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by sanju09 » Wed Nov 16, 2011 4:19 am
user123321 wrote:
sanju09 wrote:x + 2 y + 3 z = 2

x + y - z = 0

2 x + 2 y - z = 0

What is the value of y in the system above?
(A) -2
(B) -1
(C) 0
(D) 1
(E) 2
from 2nd and 3rd equation, z = 0
subtract 2nd from 1st, which gives y = 2

IMO E
oh! quick
The mind is everything. What you think you become. -Lord Buddha



Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001

www.manyagroup.com