SOLUTION: For what value of the constant k does the quadratic 2x^2 - 5x + k= 0 have a double root?

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Question 1023627: For what value of the constant k does the quadratic 2x^2 - 5x + k= 0 have a double root?
Answer by ikleyn(52778) About Me  (Show Source):
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For what value of the constant k does the quadratic 2x^2 - 5x + k= 0 have a double root?
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Calculate the discriminant d = b%5E2+-+4ac = (-5)^2 - 4*2*k = 25 - 8k.

The double root will happen when the discriminant is zero: d = 0.

It gives k = 25%2F8.