I'm not sure if I've put this in the correct section, but here goes...

Please may someone help me with this question. I understand how to do (a) but not (b).

The gradient of a curve at the point (x,y) is given by the differential equation

dy/dx = (2-x)/y

a) Find the general solution of dy/dx = (2-x)/y

b) Given that the curve passes through the point (4,2) show that the curve is a circle and find its radius and the coordinates of its centre.

Thank you all

Rachel