SOLUTION: If k = (x + 3)/(x - 4) and k^2 - 3k = 28, find k.

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Question 1208851: If k = (x + 3)/(x - 4) and k^2 - 3k = 28,
find k.

Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!

Why even bother with saying  k = (x + 3)/(x - 4)? 
since you only want k?

k%5E2+-+3k+=+28 then

k%5E2+-+3k+-+28=0

%28k-7%29%28x%2B4%29=0

k-7=0; k+4=0
  k=7;   k=-4  <--- Answers

You don't seem to care what x is, only k.  But if you did you could plug in

k+=+%28x+%2B+3%29%2F%28x+-+4%29 and get x=31%2F6 if k=7 and x=13%2F5 if x=-4.

Edwin