Algebramedium · Past Paper
What is the value of k for which the equation 4x^2 - 12x + k = 0 has equal roots?
A9
B3
C6
D36
✓ Correct Answer: A — 9
D = (-12)^2 - 4(4)(k) = 0 => 144 - 16k = 0 => k = 9.
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