Given that the square difference of the two equations x ^ 2-4x + 6K = 0 is equal to 8, then K is equal to 0 I got half of it

Given that the square difference of the two equations x ^ 2-4x + 6K = 0 is equal to 8, then K is equal to 0 I got half of it

X1^2 - X2^2 = 8
(X1 + X2)(X1 - X2) = 8
According to Weida's theorem: X1 + x2 = 4
So 4 (x1 - x2) = 8
Then X1 - x2 = 2
And (x1 - x2) ^ 2 = (x1 + x2) ^ 2 - 4x1x2 = 4 ^ 2 - 24K = 16 - 24K
So 16 - 24K = (x1 - x2) ^ 2 = 2 ^ 2 = 4
So k = 1 / 2