A point moves so that the distance between the feet of the perpendiculars from it on the pair of non parallel straight lines given by bx^2 + 2hxy + by^2 = 0 is a constant 2 units. Show that the equation to its locus is x^2 + y^2 = 4h^2/(h^2 - b^2)

I tried to solve it but each time, I ended up with an equation which was not a circle. Can anyone help?

P.S.

(The original thread seems to have disappeared)