If ax+b=0 is x>0?
1) a+b>0
2) a-b > 0
OA: E
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Hi Mo2men,
We're told that (A)(X) + B = 0. We're asked if X is greater than 0. This is a YES/NO question. This question can be solved by TESTing VALUES
From the given equation, we have a few possibilities to consider:
A and B are both 0
X and B are both 0
All 3 variables are 0
(A)(X) = -B
1) (A + B) > 0
IF...
A=1, B=0 and X=0 then the answer to the question is NO.
A=1, B= -1/2 and X=1/2 then the answer to the question is YES.
Fact 1 is INSUFFICIENT
2) (A - B) > 0
IF...
A=1, B=0 and X=0 then the answer to the question is NO.
A=1, B= -1/2 and X=1/2 then the answer to the question is YES.
Fact 2 is INSUFFICIENT
Combined, we already have 2 values that 'fit' both Facts (and product different answers - one "NO" and one "YES").
Combined, INSUFFICIENT
Final Answer: E
GMAT assassins aren't born, they're made,
Rich
We're told that (A)(X) + B = 0. We're asked if X is greater than 0. This is a YES/NO question. This question can be solved by TESTing VALUES
From the given equation, we have a few possibilities to consider:
A and B are both 0
X and B are both 0
All 3 variables are 0
(A)(X) = -B
1) (A + B) > 0
IF...
A=1, B=0 and X=0 then the answer to the question is NO.
A=1, B= -1/2 and X=1/2 then the answer to the question is YES.
Fact 1 is INSUFFICIENT
2) (A - B) > 0
IF...
A=1, B=0 and X=0 then the answer to the question is NO.
A=1, B= -1/2 and X=1/2 then the answer to the question is YES.
Fact 2 is INSUFFICIENT
Combined, we already have 2 values that 'fit' both Facts (and product different answers - one "NO" and one "YES").
Combined, INSUFFICIENT
Final Answer: E
GMAT assassins aren't born, they're made,
Rich
