ECZ 2013 · O-Level Paper 1 — Quadratic Equations
Solve the equation (x - 1)(x + 1) = 8.
- A. x = 3
- B. x = 3 or x = -3
- C. x = 9 or x = -9
- D. x = √7 or x = -√7
Verified working — step 1
Expanding the left side gives a difference of two squares - then solve x2 = 9 BOTH ways.The full step-by-step working and final answer are included with Premium — checked against ECZ marking standards.
Original examination question © Examinations Council of Zambia. Worked solution and commentary © G12 Titan — not to be reproduced without permission.
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