2'3 Complementary and Supplementary Angles 102808

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2.3 Complementary and Supplementary Angles
10/28/08

• Complementary angles the sum of two angles is
  90.
• Each angle is the complement of the other.
• Angle A and Angle B are complementary angles.

32
58
A
B
2
Supplementary Angles

• Supplementary Angles the sum of two angles is
  180.
• Each angle is the supplement of the other.
• Angle C and Angle D are supplementary angles.

46
134
C
D
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Identify Complements and Supplements

• Determine whether the angles are complementary,
  supplementary, or neither.
• a.
• a. Because 22 158 180, the angles are
  supplementary.

22
158
4
Identify Complements and Supplements

• Determine whether the angles are complementary,
  supplementary, or neither.
• b.
• b. Because 15 85 100, the angles are
  neither complementary or supplementary.

15
85
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Identify Complements and Supplements

• Determine whether the angles are complementary,
  supplementary, or neither.
• c.
• c. Because 55 35 90, the angles are
  complementary.

55
35
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Adjacent Angles

• Two angles are adjacent angles if they share a
  common vertex and side, but have no common
  interior points.
• and are adjacent
  angles.

Common side
1
2
Common Vertex
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Adjacent Angles

• Tell whether the numbered angles are adjacent or
  nonadjacent.
• a.
• Because the angles do not share a common vertex
  or a common side, then
• and are nonadjacent.

2
1
8
Adjacent Angles

• Tell whether the numbered angles are adjacent or
  nonadjacent.
• b.
• Because the angles share a common vertex and a
  common side, and they do not have an common
  interior points, and
• are adjacent.

3
4
9
Adjacent Angles

• Tell whether the numbered angles are adjacent or
  nonadjacent.
• c.
• Although and
  share a common vertex, they do not share a common
  side. Therefore, andare
  nonadjacent.

5
6
10
Measures of Complements and Supplements

• is a complement of , and
• Find
• b. is a supplement of ,and
• Find

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Measures of Complements and Supplements

• SOLUTION!
• a. and are
  complements, so their sum is 90

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Measures of Complements and Supplements

• SOLUTION!
• b. and are
  supplements, so their sum is 180

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More Practice!!!

• Textbook p. 70 71 3 26 ALL.
• Homework worksheet 2.3