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Find the sum of all possible positive integer values of $b$ such that the quadratic equation $2x^2 + 5x + b = 0$ has rational roots.

 Jun 30, 2019
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\(\text{Rational roots will occur when the discriminant is a non-negative perfect square}\\ D=b^2 - 4ac = 25-(4)(2)(b) = 25-8b\\ \text{$D$ is a perfect square for $b=0, 2, 3$}\\ \sum b = 5\)

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 Jun 30, 2019

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