Download 15 Describe Angle Pair Relationships

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Describe Angle Pair Relationships
Basketball.wmv
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Vertical Angles
2 <'s are vertical <'s if their sides form 2 pairs of opposite rays.
Example
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1 2
4
<1 and <2 are vertical <'s
<3 and <4 are vertical <'s
If 2 angles are vertical angles, then they are congruent.
Example from above:
<1 ≅ <2
and <3 ≅ <4
Check out this interactive site!
http://www.mathwarehouse.com/geometry/angle/vertical­angles.php
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Linear Pair
Adjacent angles whose noncommon sides form opposite rays. Angles add to 1800
example:
1 2
<1 & <2 are linear pairs
Complementary <'s
Sum of the angles measures = 900
700
or
20
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Supplementary Angles
Sum of the measures = 1800
1200
600
Example:
Identify all of the linear pairs and all of the vertical angles in the figure.
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4
Linear Pairs
2
7
1
5 6
8
9
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Vertical Angles
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Examples:
1.) <ABD and <DBC are complementary <'s. Find the value of the variable & angle measures.
A
D
8n
B
7n
C
2.) If <1 & <2 are supplementary. Suppose that m<1 = 600 and m<2 = (2x + 20)0
What is the value of x?
3.) Two angles form a linear pair. The measure of one angle is 3 times the measure of the other. Find the measure of each angle.
4.) Find the value of x and all of the angle measures.
5.) Find the values of x and y
18y
7x­2
11x­34
0
(20x+5)
15x
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Homework:
p. 39­41/8­16 Even, 17­27, 28(Show your let statements),33­39, 42, 53
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Attachments
Basketball.wmv