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Question

Can anyone solve this pls?

gk3.14 · Answer

ax + b = 0 => implies x = -b/a

Is x> 0?

1. a + b> 0 
a is positive, b is positive x is -ve or < 0
a is negative and b is postive x -ve 
a is postive and b is negative x +ve or > 0

INSUF

2. a -b > 0 ; a > b

a is positive b is positive x is -ve
a is positive b is negative x is +ve

INSUF

Combined we get a>0 or positive or b is positive..Let's try one:
but if b is positive x is negative
if b is negative x is positive
So INSUF

Answer E;

Professor · Answer

from i and ii, we only know that a >0 but b could be +ve or -ve. so does x. 

E.

ps_dahiya · Answer

E

Stem says ax+b = 0 i.e b = -ax

St1: a+b > 0 i.e a-ax>0
a(1-x) > 0....EQ1
x could be anything depending on the value of a.: INSUFF

St2: a-b > 0 i.e a+ax>0
a(1+x) > 0....EQ2
x could be anything depending on the value of a.: INSUFF

Together:
Adding equation 1 and 2 we get
2a>0
i.e a>0
if a is greater than 0 then 
from EQ1 we can say that (1-x) > 0 i.e x < 1
from EQ2 we can say that (1+x) > 0 i.e x>-1
so 1>x>-1: INSUFF

trivikram · Answer

take a+b>0

a-b>0


and divide them by a

you get E

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