I apologise if this is in the wrong section, but it was under my homework: Algebra.

Two circles C1 and C2 are members of a set of circles defined by this equation: [/tex] x^2 + y^2 - 6x + 2ky + 3k = 0 [tex]. The centre of C1 lies on the line x - 3y = 0 and C2 touches the x axis. Find the equations of C1 and C2

so how would I use algebra to do this