SOLUTION: For what value of k are the roots of 2x^2-8x+k=0 equal?

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Question 363323: For what value of k are the roots of 2x^2-8x+k=0 equal?
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
2x%5E2-8x%2Bk=0 is the same as x%5E2-4x%2Bk%2F2=0 after division by 2. The product of the roots is r%2Ar+=+r%5E2+=+k%2F2, while the sum of the roots is r%2Br+=+2r+=+-%28-4%29+=+4. Thus r+=+2, and 4+=+k%2F2, and thus k+=+8.