Algebrahard · Past Paper
Find the values of k for which x^2 - (k+4)x + 2k + 5 = 0 has equal roots.
A2, -2
B±√2
C±6
D±4
✓ Correct Answer: A — 2, -2
D = (k+4)^2 - 4(2k+5) = 0 → k^2 + 8k + 16 - 8k - 20 = 0 → k^2 - 4 = 0 → k = ±2.
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