For the transformation w=1/(z-2), where z=x+iy and w=u+iv,

show that the straight line 2x+y=5 is transformed to a circle with centre (1,-0.5) and radius 0.5sqrt5.

I can get to the stage where I equate the real and imaginary parts, but I can't see how to use the information about the original image, i.e the straight line 2x+y=5.

Any help would be greatly appreciated, thanks.