

1. A perpendicular bisector of a segment (by definition) is a line that is perpendicular to the segment and intersects the segment at its midpoint.

2. because a midpoint of a segment divides the segment into two congruent segments.

3. AD = DB because congruent segments are segments of equal measure.

4. The line of reflection for a segment is the perpendicular bisector of the segment.

5. Under a reflection in , A is mapped onto B, C is mapped onto C, and D is mapped onto D.

6. Under a reflection in , is mapped onto .

7. CA = CB since a reflection is a rigid transformation which preserves length. 