If ax+b=0, is x>0?
1) a+b>0
2) a-b>0
ax = -b
1. a + b > 0
= a -ax > 0
= a(1-x) > 0
= a > 0 AND (1-x) > 0 OR a < 0 AND (1-x) < 0
= a > 0 AND 1 > x OR a < 0 AND 1 < x => x can be less than 1 or x is greater than 1....So can not answered..
2. a - b > 0
= a + ax > 0
= a(1+x) > 0
= a > 0 AND (1+x) > 0 OR a < 0 AND (1+x) < 0
= a > 0 AND x > -1 OR a < 0 AND x < -1 => x can be greater than -1 or x is less than -1...so can not be answered...
Is my work till this point fine?
N how to club the these two statements...
OA E
Inequality
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- Gurpinder
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your doing too much adi....
If ax+b=0, is x>0?
rephrase the question first
ax=-b
x=-b/a
1) a+b>0
a>-b
insuficient.
2) a-b>0
a>b
insufficient.
together:
insufficient.
hence (E)
If ax+b=0, is x>0?
rephrase the question first
ax=-b
x=-b/a
1) a+b>0
a>-b
insuficient.
2) a-b>0
a>b
insufficient.
together:
insufficient.
hence (E)
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- selango
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adi ur steps are fine.adi_800 wrote:If ax+b=0, is x>0?
1) a+b>0
2) a-b>0
ax = -b
1. a + b > 0
= a -ax > 0
= a(1-x) > 0
= a > 0 AND (1-x) > 0 OR a < 0 AND (1-x) < 0
= a > 0 AND 1 > x OR a < 0 AND 1 < x => x can be less than 1 or x is greater than 1....So can not answered..
2. a - b > 0
= a + ax > 0
= a(1+x) > 0
= a > 0 AND (1+x) > 0 OR a < 0 AND (1+x) < 0
= a > 0 AND x > -1 OR a < 0 AND x < -1 => x can be greater than -1 or x is less than -1...so can not be answered...
Is my work till this point fine?
N how to club the these two statements...
OA E
a-ax>0-->Eqn1
a+ax>0-->Eqn2
Eqn1+Eqn2 gives a>0
Eqn1-->1-x>0 or x<1
Eqn2-->1+x>0 or x>-1
-1>x<1
X can be -0.5 or 0.5
We don't know value of x.Insufficient
--Anand--
- arora007
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your steps are fine... Plugging in values, and u will see that the values can neither be A nor be B, it a C or E question.adi_800 wrote:If ax+b=0, is x>0?
1) a+b>0
2) a-b>0
ax = -b
1. a + b > 0
= a -ax > 0
= a(1-x) > 0
= a > 0 AND (1-x) > 0 OR a < 0 AND (1-x) < 0
= a > 0 AND 1 > x OR a < 0 AND 1 < x => x can be less than 1 or x is greater than 1....So can not answered..
2. a - b > 0
= a + ax > 0
= a(1+x) > 0
= a > 0 AND (1+x) > 0 OR a < 0 AND (1+x) < 0
= a > 0 AND x > -1 OR a < 0 AND x < -1 => x can be greater than -1 or x is less than -1...so can not be answered...
Is my work till this point fine?
N how to club the these two statements...
OA E
now when you want to combine in equalities, add them up...
a+b>0 ADDED TO a-b>0
gives 2a >0 which means a>0
now assume values a=1 , case 1) then b could be 1, 10 , 0.1, -0.1
for which x would be -1, -10, -0.1 or 0.1
thus does not suffice!
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Few things are impossible to diligence & skill.Great works are performed not by strength,but by perseverance
pm me if you find junk/spam/abusive language, Lets keep our community clean!!