Which one of the following equations does <strong>NOT</strong> have real roots?
- A. 2x^{2}+16x+3=0
- B. 2x^{2}+10x-1=0
- C. x^{2}-8x+1=0
- D. 4x^{2}+9x+6=0 ✓
Correct Answer: D. 4x^{2}+9x+6=0
Explanation
For an equation to lack real roots, its discriminant must be negative (b^2 - 4ac \lt 0). In option (d), \Delta = 9^2 - 4(4)(6) = 81 - 96 = -15, which is less than 0.
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