Find the sum of all possible positive integer values of b such that the quadratic equation 2x^2 + 15x + b = 0 has rational roots.
+128408 For this to have rational roots, the discriminant must be a perfect square
So
15^2 - 4 (2)b must be a perfect square
225 - 8b
When b = Perfect Square
7 169
81/8 144
13 121
125/8 100
18 81
161/8 64
22 49
189/8 36
25 25
209/8 16
27 9
221/8 4
28 1
225/8 0
Sum of the positive integer "b" values = 7 + 13 + 18 + 22 + 25 + 27 + 28 = 140
