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The sum and product of the roots of a quadratic equation are (frac{4}{7}) and (frac{5}{7})…

The sum and product of the roots of a quadratic equation are (frac{4}{7}) and (frac{5}{7}) respectively. Find its equation.

  • A.
    (7x^{2} – 4x – 5 = 0)
  • B.
    (7x^{2} – 4x + 5 = 0)
  • C.
    (7x^{2} + 4x – 5 = 0)
  • D.
    (7x^{2} + 4x + 5 = 0)
Correct Answer: Option B
Explanation

Let the roots of the equation be (alpha) and (beta).

(alpha + beta = frac{-b}{a} = frac{4}{7})

(alpha beta = frac{c}{a} = frac{5}{7})

(implies a = 7, b = -4, c = 5)

Equation: (ax^{2} + bx + c = 0 )

= (7x^{2} – 4x + 5 = 0)