SOLUTION: find the value of k. x^2+kx-21=0 when one root is 7

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Question 245065: find the value of k. x^2+kx-21=0
when one root is 7
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
x^2+kx-21
(x+7)(x-3)
x^2+4x-21
k=4 ans.