1: Point Q is the perpendicular bisector on MN
Given.
2. MX = MX
Definition of bisector
3. <QXM and <QXN are right angles
Definition of perpendicular.
4. <QXM = <QXN
All right angles are congruent.
5.QX = QX
Reflexive Property of Congruence
6. Triangle QXM = Triangle QXN
SAS Congruence Postulate.
7. QM = QN
Corresponding parts of congruent triangles are congruent.