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singhmaharaj
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Target question: Is x > 0?singhmaharaj wrote:If ax + b = 0, is x > 0?
(a) a + b > 0
(b) a - b > 0
Given: ax + b = 0
Statement 1: a + b > 0
These statements "feel" insufficient, so I'm going to start TESTING values.
There are several values of a, x and b that satisfy this condition. Here are two:
Case a: a = 2, x = 1/2, and b = -1, in which case x IS greater than 0
Case b: a = 2, x = -1/2, and b = 1, in which case x x is NOT greater than 0
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: a - b > 0
There are several values of a, x and b that satisfy this condition. Here are two:
Case a: a = 2, x = 1/2, and b = -1, in which case x IS greater than 0
Case b: a = 2, x = -1/2, and b = 1, in which case x x is NOT greater than 0
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined
There are several values of a, x and b that satisfy BOTH statements. Here are two:
Case a: a = 2, x = 1/2, and b = -1, in which case x IS greater than 0
Case b: a = 2, x = -1/2, and b = 1, in which case x is NOT greater than 0
Since we cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT
Answer = E
Cheers,
Brent
