Question: Is xy > 0?

Question REPHRASED: DO X AND Y HAVE SAME SIGNS ?

Statement 1: x = y + 6

Case 1: at y = -1, x = 5 i.e. xy < 0
Case 2: at y = +1, x = 7 i.e. xy > 0

NOT SUFFICIENT

Statement 2:y < 0

No relation of y with x is given yet therefore we are inconclusive about sign of x hence

NOT SUFFICIENT

COmbining the statements

y < 0 and x = y + 6

Case 1: at y = -1, x = 7 i.e. xy < 0
Case 2: at y = -10, x = -4 i.e. xy > 0

NOT SUFFICIENT

Answer: Option E
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Is xy > 0 ?

(1) x = y + 6
(2) y < 0

xy>0 ==> (x>0, y>0); (x<0, y<0) == to find

1. x= y+6
take y=1, we get x=7 ==> x>0, y>0 : sufficient
take y=-1, we get x=5 ==> x>0, y<0 : not sufficient
therefore, not A

2. y<0
no information about x
if x>0 : not sufficient (as x>0, y<0)
if x<0 : sufficient (as x<0, y<0)
therefore, not B
obviously, not D

we have to choose from from C and E
combining 1 and 2, we have

y<0 and x=y+6
take y=-10, we get x=-4; x<0, y<0 : sufficient
take y=-1, we get x=5; x>0, y<0 : not sufficient

therefore, E

target find xy>0
#1
x=y+6
x-y=6
x =0 ; y = -6
x=4 ; y = -2
x=7 ; y=1
insufficient
#2
y<0
x not know insufficient
from 1 &2
y is -ve
so
x =0 ; y = -6
x=4 ; y = -2
OPTION E

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