Answer:
2. RS ≅ ST (Definition of midpoint).
- Definition of midpoint states that the point shared by both line segment (in this case, S, is your mid point, and that (in this case, R & T), are end points.
4. RS ≅ XY (Transitive Property of Congruence).
Transitive Property of Congruence state that if you know that, for example, XY ≅ RS, & ST ≅ RS, therefore, XY ≅ ST (Transitive Property).
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