Examine the nature of the roots of $x^2+8x+16=0$.
AReal and distinct
BReal and equal
CImaginary and conjugate
DReal, irrational and distinct
Answer & Solution
Correct answer: B. Real and equal
For $x^2+8x+16=0$, the discriminant is $D=b^2-4ac=8^2-4\cdot1\cdot16=64-64=0$. When the discriminant is zero, the quadratic has real and equal roots. In fact, the equation factors as $(x+4)^2=0$.
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