Algebrahard · Past Paper
If roots of ax^2 + bx + c = 0 are in ratio 2:3, then:
A6b^2 = 25ac
B25b^2 = 6ac
Cb^2 = ac
D6b = 25ac
✓ Correct Answer: A — 6b^2 = 25ac
Let roots be 2k, 3k. Sum 5k = -b/a, Product 6k^2 = c/a. Replace k: 6(-b/5a)^2 = c/a => 6b^2/25a^2 = c/a => 6b^2 = 25ac.
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