Find the particular solution for dy/dx=(y-5)/x, using the point y(0)=7

I got y-5=Ax (or ln(y-5)=ln(x)+c)

For both of which there is no way to find A or c...I had this question in a test, and wrote it was impossible to find the particular solution with the given point (I believe the examiner made an error..) am I correct?