passwella.
Menu

WAEC Further Mathematics 2026 Question 1

Question 1

Matrices and Determinants

If X = (2 3 / 1 4), Y = (1 5 / 0 3) and Z = (6 −1 / 1 2), find 5X − 2Y + 2Z. (Each matrix is written row by row; / separates the rows.)

  1. A.(−4 7 / 3 10)
  2. B.(4 7 / 3 −10)
  3. C.(20 3 / 7 18)
  4. D.(−20 3 / 7 −18)
Show the answer and explanation

Answer: C ((20 3 / 7 18))

Explanation

5X = (10 15 / 5 20), 2Y = (2 10 / 0 6), 2Z = (12 −2 / 2 4). So 5X − 2Y + 2Z = (10 − 2 + 12, 15 − 10 − 2 / 5 − 0 + 2, 20 − 6 + 4) = (20 3 / 7 18).