Algebraeasy · Past Paper
The value of k for which x^2 - 4x + k = 0 has equal roots is:
A2
B4
C-4
D16
✓ Correct Answer: B — 4
For equal roots, D = 0. (-4)^2 - 4(1)(k) = 0 => 16 - 4k = 0 => k = 4.
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