greater is x than y

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greater is x than y

by sanju09 » Mon Jul 26, 2010 2:31 am
If x and y are both positive integers, how much greater is x than y?

1. x + y = 20.
2. x = y².

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by kvcpk » Mon Jul 26, 2010 2:39 am
sanju09 wrote:If x and y are both positive integers, how much greater is x than y?

1. x + y = 20.
2. x = y².

[spoiler]Source: majortests.com[/spoiler]
x + y = 20.
No info about x-y. INSUFF

x=y^2
x=9, y=3 -> diff is 6
x=4, y=2 -> diff is 1
INSUFF

Combining:
20-y = y^2
y = 4 or y = -5
BUt X,y are positive integers.
Hence y=4
x= 16

SUFF

pick C

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by outreach » Mon Jul 26, 2010 4:11 am
C

stmt 1
gives no info abt diff between x and y

stmt 2
difference will vary based on number


combined
y^2+y-20=0
y=-5,or 4

since x and y r positive y=4..x =16
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by avinash100 » Mon Sep 12, 2011 1:45 pm
x+y=20
X=Y^2
y^2+Y-20=0
Y^2+5y+4y-20=0
Y(Y+5)-4(y+5)=0
Y+5=0 so, y=-5
Y-4=0 Y=4 +integer
X+y=20
16+4=20