Chapter 1.4 Segments .notebook
September 12, 2014
1.4 Measuring Segments
Objective: To find the lengths of segments
N.2.D.
Performance Standard 1.6, 3.4, 3.5 DOK­1, 2
Knowledge MA 3
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Chapter 1.4 Segments .notebook
September 12, 2014
Ruler postulate: The distance between any two points is measureable.
A segment has two ENDPOINTS, therefore it can be MEASURED!
Segment AB = 3 inches long
A
B
If segments can be measured, then their lengths can be compared. If two segments have the same length then we say the segments are CONGRUENT.
Congruent segments: two segments with the same length. Actual measurements are considered EQUAL not congruent.
Use the congruent symbol with letters:
Use the equal signs with numbers:
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Chapter 1.4 Segments .notebook
September 12, 2014
E
A
B
C D
­8
­5
­2 0 3
1) Find AC.
2) Find BE.
3) Find CE.
4) AB ≅ ______.
Assignment: Worksheet 1.4 2,4,42,44,46
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Chapter 1.4 Segments .notebook
September 12, 2014
Segment Addition postulate: If 3 points are collinear, then AB + BC = AC.
C
B
A
An important fact of understanding geometric figures: coding and labeling!!! Mark all information in a figure that you understand from the information given.
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Chapter 1.4 Segments .notebook
September 12, 2014
Examples: Label and code all information. Solve for the value(s).
5) A
C
T
6)
D
7)
E
S
T
F
G
CT= 10
AT=2
CA=?
DT=60
DS=2x­8
ST=3x­12
X=
DS=
DT=
EF=2x­6
FG=x+7
EG=25
x=
EF=
FG=
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Chapter 1.4 Segments .notebook
September 12, 2014
Midpoint­ the point that divides a segment into two congruent segments. M is the modpoint of AB. Label and code.
8) 9)
D
P
O
T
G
Q
O is the midpoint of DG. DO= 2x+11
OG=3x­4 Find:
DO=
OG=
DG=
T is the midpoint of PQ.
PT= 5x+3
TQ=7x­9
Find PT.
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Chapter 1.4 Segments .notebook
September 12, 2014
10) C is the midpoint of AB. AC = 2x + 1 and CB = 3x ­ 4. Find AC, BC and AB. Draw a picture and label. Show all work. Box answers.
Assignment: Complete remainder of worksheet 1.4
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Chapter 1.4 Segments .notebook
September 12, 2014
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