Is the sum of the roots of the equation, x^2 + bx + c = 0, positive?

Question

(1) b < 0
(2) c < 0

aragonn · Answer

sum = -b
depending on the value of b , sum will be decide, A is correct.

GMAT215 · Answer

I was not knowing that it was that simple, found this on gooogle, hope it helps

GMATinsight · Answer

For any quadratic equation ax^2 + bx + c = 0

the sum of the roots = -b/a

Here, comparing x^2 + bx + c = 0 with ax^2 + bx + c = 0

we find, a = 1, b = b and c = c

now Sum of the roots = -b/1 = -b

For sum of the roots to be positive, b must be Negative

Statement 1: b < 0

SUFFICIENT

Statement 2: c < 0

No information about b hence

NOT SUFFICIENT

Answer: option A

shrik · Answer

ALWAYS REMEMBER

For any given quadratic equation ax^2 +bx+c

1. SUM OF ROOTS OF QUADRATIC EQUATION IS  -b/a

2.PRODUCT OF ROOTS OF QUADRATIC EQUATION IS  c/a

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