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Source: — Data Sufficiency |

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by DanaJ » Sun Jan 18, 2009 12:05 am
(1) is the equivalent of B being either 0 or 4:
a. B = 0, then you have F(x) = x^2. If F(C) = 0, then C can only be 0. But that does not fit the description of C<0, so C cannot be 0.
b. B = 4, giving you F(x) = x^2 + 4x + 4 = (x +2)^2. F(C) = 0 only if C+2 = 0, giving us C = -2, which is less than 0.
So C can only be -2, meaning that A is the correct answer.