Answer:
The answer is D.
Step-by-step explanation:
We have to apply Discriminant Law. When a quadratic equation, ax² + bx + c = 0 has equal roots so the discriminant will be 0. Then, you have to substitute the values into the formula :
[tex]D = {b}^{2} - 4ac[/tex]
[tex]let \: D = 0 ,a = 2,b = k,c = k[/tex]
[tex]0 = {k}^{2} - 4(2)(k)[/tex]
[tex] {k}^{2} - 8k = 0[/tex]
[tex]k(k - 8) = 0[/tex]
[tex]k = 0[/tex]
[tex]k - 8 = 0[/tex]
[tex]k = 8[/tex]
