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krishna239455
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ax + b = 0 implies b = -axkrishna239455 wrote:Pls help
Question is: Is x > 0?
(1) a + b > 0 implies a - ax > 0 or a(1 - x) > 0 implies either a > 0 and 1 - x > 0, so x < 1 or a < 0 and 1 - x < 0, so x > 1.
No definite answer; NOT sufficient.
(2) a - b > 0 implies a + ax > 0 or a(1 + x) > 0 implies either a > 0 and 1 + x > 0, so x > -1 or a < 0 and 1 + x < 0, so x < -1.
No definite answer; NOT sufficient.
Combining (1) and (2), (a + b) + (a - b) > 0 implies a > 0
So, x < 1 and x > -1 implies -1 < x < 1, which implies x may or may not be negative; NOT sufficient.
The correct answer is E.
