ECZ 2018 · GCE Paper 1 — Variation
Two variables x and y are such that y = 4(x2 + 1). Given that y = 104 when x = a, find the values of a.
- A. 5
- B. 25
- C. ±6
- D. ±5
Verified working — step 1
Substitute y = 104, then peel the layers off a2 one at a time - and keep BOTH square roots.The full step-by-step working and final answer, plus the video lesson for this topic, 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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