1.5 Measuring Segments 2010 August 27, 2010
1.5 Measuring Segments
Objective: Find the lengths of segments.
Aug 18 ­ 7:47 PM
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1.5 Measuring Segments 2010 August 27, 2010
Check Skills You'll Need
Simplify each absolute value expression.
1) |­6|
2) |3.5|
Solve each equation.
3) |7­10|
6) x + 2x ­ 6 = 6
4) |­4 ­ 2|
5) |­2 ­ (­4)|
7) 3x + 9 + 5x = 81
Aug 25­2:33 PM
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1.5 Measuring Segments 2010 August 27, 2010
Congruent Segments: Segments that have the same length.
Example:
3 cm
A
3 cm
B
C
D
Written as: AB ≅ CD
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1.5 Measuring Segments 2010 August 27, 2010
Example: Find the lengths of the following segments. Tell whether the segments are congruent.
AD and BE
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1.5 Measuring Segments 2010 August 27, 2010
Describe Segment Relationships
Step 1: Name all of the segments in the following figure.
X
Y
Z
Step 2: Describe the relationships between the different segments.
Step 3: What relationship always applies to a figure like this?
(Even if point Y was placed somewhere else between X and Z.)
Aug 23­8:25 PM
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1.5 Measuring Segments 2010 August 27, 2010
Example:
Aug 25­2:50 PM
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1.5 Measuring Segments 2010 August 27, 2010
Midpoint (of a segment): The point that divides the segment into two congruent segments.
Example: B is the midpoint of AC.
Aug 21­1:20 PM
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1.5 Measuring Segments 2010 August 27, 2010
Example:
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1.5 Measuring Segments 2010 August 27, 2010
Homework:
page 33 (2 ­ 18 even, 30 ­ 36 even)
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