Algebra & Equations · Question 14 · Hard
For what positive value of k does the equation x² − kx + 16 = 0 have equal roots?
- 16
- 4
- 64
- 8
Answer and explanation
Answer: D. 8
Explanation: Equal roots need discriminant = 0: k² − 4 × 16 = 0, so k² = 64 and k = 8.
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