SOLUTION: Use the discriminant to determine all values of k that would result in the equation x^2 − kx + 4 = 0 having equal roots.

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Question 462637: Use the discriminant to determine all values of k that would result in the equation
x^2 − kx + 4 = 0 having equal roots.


Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
The discriminant is %28-k%29%5E2+-+4%2A1%2A4. Equating it to zero for equal roots, we get %28-k%29%5E2+-+4%2A1%2A4+=+0 <==> k%5E2+=+16, or k = -4, 4.