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# Help plz

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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

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