Question 612440
<pre>
Suppose this green circle is of radius 3 units:
{{{drawing(200,200,-4,4,-4,4, green(circle(0,0,3)) )}}}
Then the locus of all points which are 1 unit distance 
(radially) from each point on that green circle are these 
two red circles, one inside of radius 2 units and one 
outside of radius 4 units.
{{{drawing(200,200,-4,4,-4,4, green(circle(0,0,3)),
red(circle(0,0,2),circle(0,0,4))

 )}}}

Edwin</pre>