SOLUTION: Find k so that x+2 is a factor of x^3 - kx^2 + 3x + 7k Thanks so much in advance:)

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Question 825645: Find k so that x+2 is a factor of x^3 - kx^2 + 3x + 7k
Thanks so much in advance:)
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
Find k so that x+2 is a factor of x³ - kx² + 3x + 7k

Use synthetic division:

-2 | 1   -k      3   7k
   |     -2   2k+4  -4k-14
     1 -k-2   2k+7   3k-14

The remainder 3k-14 must equal 0 if x+2 is to be a factor.

So we set  3k-14 = 0
              3k = 14
               k = 14%2F3

Edwin