passwella.
Menu

WAEC Mathematics 1998 Question 8

Question 8

Quadratic Equations

Solve the equation 5x2 − 4x − 1 = 0

  1. A.−1, 1/5
  2. B.−1, −1/5
  3. C.1, 1/5
  4. D.1, −1/5
  5. E.−1, 5.
Show the answer and explanation

Answer: D (1, −1/5)

Explanation

5x2 − 4x − 1 = (5x + 1)(x − 1) = 0, so x = 1 or x = −1/5.