ECZ 2017 · O-Level Paper 1 — Quadratic Equations
If y = (1 − 2x)(1 + x) − 2, find the values of x for which y = −2.
- A. x = ½ or x = −1
- B. x = −½ or x = 1
- C. x = 2 or x = −1
- D. x = ½ or x = 1
Verified working — step 1
Set y = −2: (1 − 2x)(1 + x) − 2 = −2, so (1 − 2x)(1 + x) = 0. A product is zero when a factor is zero: 1 − 2x = 0 gives x = ½, or 1 + x = 0 gives x = …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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