If the solution of the first order equation x = kx-4 and the equation x-3 = 3x + 1, k =?

If the solution of the first order equation x = kx-4 and the equation x-3 = 3x + 1, k =?

Because: x-3 = 3x + 1
So: x-3x = 1 + 3
-2X=4
X=-2
Substituting x = - 2 into the original equation, we get the following result:
-2=-2K-4
2K=-4+2
2K=-2
K=-1