Question

Comment.

Answer 1

This lists your two cases (among others)
http://www.onlinemathlearning.com/locus-math.html

Answer 2

So technically...the configurations are circles.

Answer 3

there are 2 different questions

1) locus of points 3 units from the x-axis. The x-axis is a line. So you want all points 3 units from a line. See condition 3 in the link

2) locus of points 3 units from a point. see condition 1.

It you plot all of this, there will be 2 points that satisfy both questions at the same time.

Answer 4

Got it. Thanks! I have another question coming up....are you good with writing proofs?