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What is the nature of the roots of x^2 + 4x + 5 = 0?
AReal and distinct because discriminant is positive
BReal and equal because discriminant is zero
CImaginary because discriminant is negative
DRational integers because root values match
Answer & Solution
Correct answer: C. Imaginary because discriminant is negative
1. Coefficients are a = 1, b = 4, c = 5.
2. D = b^2 - 4ac = 16 - 20 = -4.
3. Negative discriminant means non-real (imaginary) roots.
4. So option A is correct.
_Source: Selina Concise Mathematics Class 10, Ch 5 Quadratic Equations (Mistral OCR'd PDF), section on nature of roots_
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