What are postulates?

A rule in geometry that is accepted without proof, it is given.

CHAPTER 1-2 (SEGMENTS AND CONGRUENCE)

Postulate 1: Ruler

Points on a line can be matched to numbers (coordinates)

Distance between points can be written as absolute value of distance between coordinates

CHAPTER 1-2 (SEGMENTS AND CONGRUENCE)

Example Measure the length of the line segment given to you (in cm). Have your shoulder partner confirm

CHAPTER 1-2 (SEGMENTS AND CONGRUENCE)

Postulate 2: Segment Addition

If B is between A and C, then AB + BC = AC

If AB + BC = AC, then B is between A and C

CHAPTER 1-2 (SEGMENTS AND CONGRUENCE)

Example

CHAPTER 1-2 (SEGMENTS AND CONGRUENCE)

Example Use the Segment Addition Postulate to write an equation, then solve to find the KL

CHAPTER 1-2 (SEGMENTS AND CONGRUENCE)

Example

CHAPTER 1-2 (SEGMENTS AND CONGRUENCE)

What are congruent segments?

Line segments that have the exact same length.

Lengths are EQUAL (AB = CD)

Segments are CONGRUENT (AB = CD)

CHAPTER 1-2 (SEGMENTS AND CONGRUENCE)

A B

C D

Example

CHAPTER 1-2 (SEGMENTS AND CONGRUENCE)