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45 votes
45 votes
Find the possible values of the constant k if the roots of the quadratic equation

x^2 - (k+2)x + 4 =0 are equal ​

User Jonas Lincoln
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1 Answer

16 votes
16 votes

Answer:


{b}^(2) - 4ac = 0 \\ { ( - k - 2)}^(2) - 4(1)(4) = 0\\ {k}^(2) + 4k + 4 - 4 = 0 \\ {k}^(2) + 4k = 0 \\ k(k + 4) = 0 \\ \therefore \: k = 0 \: or \: k = - 4

User Sarah Northway
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2.5k points