Question: What is the value of k if the quadratic equation x^2 + kx + 16 = 0 has equal roots?
Options:
Correct Answer: -4
Solution:
For equal roots, the discriminant must be zero: k^2 - 4*1*16 = 0, thus k^2 = 64, giving k = -8 or k = 8. The answer is -8.