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If the roots of the quadratic equation 2...

If the roots of the quadratic equation `2x^(2)+8x+k=0` are equal, find the value of k.

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The correct Answer is:
k=8
`D=(8)^(2)-4xx2xxk=(64-8k).`
`:." "D=0implies64-8k=0implies8k=64impliesk=8.`
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