gmatnmein2010 wrote:if y>=0 , what is the value of x?

1) lx-3l>=y

2) lx-3l<=-y

1) lx-3l>=y-------->lx-3l is either +ve or equals to 0

for +ve x>3 insuff
for 0 x=3 suff

s1 altogether gives two value of x hence insuff

2) mod of any variable is +ve and is therfore always > any -ve no.
but if y=0 then lx-3l can be =0----->x can be +3 or x can be -3
hence insuff

s1+s2=also insuff

IMO E

gmatnmein2010 wrote:if y>=0 , what is the value of x?

1) lx-3l>=y

2) lx-3l<=-y

y>=0
St.1: lx-3l>=y --> lx-3l>=0 which is always true for any x..so lots of values of x ............not suff.
St.2 lx-3l<=-y
since y>=0 --> -y<=0 --> lx-3l<=0 since lx-3l>=0
so x=3 is the only soln..-----------suff...Ans B