SOLUTION: Find the value of the constant k for which the equation 2x^2+(k+3)x+2k=0 has equal roots

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Question 1163376: Find the value of the constant k for which the equation 2x^2+(k+3)x+2k=0 has equal roots
Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
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The discriminant must be equal to zero


    d = %28k%2B3%29%5E2 - 4*2*(2k) = 0,   or

     k^2 +  6k + 9 - 16k = 0

     k^2 - 10k + 9 = 0

     (k-9)*(k-1) = 0


The roots are   k%5B1%5D = 1  and  k%5B2%5D = 9.

     

ANSWER.  The values of "k" under the problem's question are 1 and 9.

Solved.