the locus is the perpendicular bisector of the segment
Step-by-step explanation:
The points equidistant from A and B lie on the line that is the perpendicular bisector of segment AB.
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<em>Comment on this geometry</em>
You take advantage of this fact when you construct a circle through 3 points. You construct the perpendicular bisectors of segments between pairs of the points, and locate the center of your circle at their intersection.
