SOLUTION: Given one roots of x^2+px+8=0 is two times of the other. Find the roots and p.

Question 408299: Given one roots of x^2+px+8=0 is two times of the other. Find the roots and p.
Answer by richard1234(7193) (Show Source): You can put this solution on YOUR website!
Interesting thing about this problem is that the roots and the value of p are not uniquely determined. You'll see why:

Suppose the two roots are and . The product of the roots is 8 by Vieta's formulas, so --> --> r = +/- 2. Hence, the roots are {2, 4} or {-2, -4}. Also, the sum of the roots is -p, so p = -6 or 6, respectively.

Hence, the quadratic has roots {2, 4} and has roots {-2, -4}.
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