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The dilemma is the sign

Algebra Level 3

Let \(a, b\) and \(c\) be arbitrary real numbers such that \(a+b+c>0\) and \(b^{2}<4ac.\) Which of the following is right about the sign of \(a\)?

\(a\) must be always negative. \(a\) can be positive or negative but not zero. \(a\) must be always zero. \(a\) must be always positive. \(a\) can be positive, negative or zero.

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Excel in math and science

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by Arturo Presa

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