If 3x+y = k(x-3) then x=?

Question

I need help on how you would rearrange the question in terms of x

Answer 1

3x + 7 = k(x - 3)

3x + 7 = kx - 3k

3x - kx = -3k - 7

x(3 - k) = -3k - 7

x = (-3k - 7) / (3 - k)

x = (3k + 7) / (k - 3)