Engineering Board Exam Reviewer · Quadratic Equations · medium
For what values of k does x2+kx+16=0 have equal roots?
- k=8
- k= 4
- k= 16
- k= 8
Answer
D. k= 8
Solution
Equal roots require the discriminant to be zero: k2-4(1)(16)=0 k2=64 k= 8.
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