The document discusses the concept of congruent segments, stating that two segments are congruent if they have the same length. It outlines the primary theorems related to segment congruence, including reflexive, symmetric, and transitive properties. Additionally, it defines a midpoint and provides formulas for calculating the midpoint and length of segments.

1. Section 2.3

2.  Two segments are congruent if and only if
they have the same length.
 Below AB ≅ CD (“≅” means “is congruent to”)
2 cm B C 2 cm
A D

3.  Theorems are statements derived by logical
argument using definitions and accepted facts.
 Primary Theorems of segments
Congruence of Segments is: Meaning:
Reflexive AB ≅ AB
Symmetric If AB ≅ CD, then CD ≅ AB
If AB ≅ CD & CD ≅ EF,
Transitive
then AB ≅ EF

4.  A Midpoint is the point that is the same
distance from each endpoint
 For a segment with endpoints A an B, it is
found using the formula:
M=½(A+B) B
M
A

5.  Length
AB = ∣ B – A ∣ B
M
 Midpoint length formulas
A
AM = MB
AM = ½ AB
MB = ½ AB