Warm-up

1
Warm-up

• Fill in the blank with always, sometimes, or
  never.
• Explain your answer.
• A bisector of a segment is ______ a line.
• A ray ______ has a midpoint.
• 3. Congruent segments ______ have equal lengths.
• 4. If B is between A and C, then AB ________
  equals BC.

2
Lesson 1-4 Angles angle (?) a figure formed
by two rays that have the same endpoint. The two
rays are called sides of the angle. Their
common endpoint is called the vertex.
Angle name(s)
Sides
Vertex
3
acute angle an angle with measure between 0 and
90?.
obtuse angle an angle with measure between 90?
and 180?.
right angle an angle with measure 90?.
straight angle an angle with measure 180?.
4
(No Transcript)
5
Use a protractor to measure each angle to the
nearest degree. Then, write three names for each
angle.
6
Postulate 4 Angle Addition Postulate If
point B lies in the interior of ?AOC, then m?AOB
m?BOC m?AOC .
m?AOB m?BOC 180? .
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HOMEWORK 4

• page 20
• CLE 28-33 all
• page 21
• WE 1-22 all, 26-28 all

8
Warm-up
1. Name the vertex of ?3. 2. Name a right
angle. State another name for each angle. 3. ?1
4. ?BDC 5. ?3 6. ?DBC 7. ?7 8. ?2 9.
?AEB 10. ?5
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Lesson 1-4 Angles (continued)
congruent angles angles that have equal
measures.
congruence marks
If m?A m?B, then ?A ? ?B.
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adjacent angles (adj. ?s) two angles in a plane
that have a common vertex and a common side but
no common interior points.
?1 and ?2 are adjacent angles.
?3 and ?4 are NOT adjacent angles.
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bisector of an angle the ray that divides the
angle into two congruent adjacent angles.
?MNO ? ?ONP.
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Ex. 1) Find each angle measure, given the
diagram and information below.
Given m?1 5x, m?2 (x 40), and
m?3 (x 2 20)
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Given m?RAM (5x 7), and m?MAS
(x 3)
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HOMEWORK 5

• page 22 29-36 all
• Read pages 22-23 and complete the outline of
  Lesson 1-5, including all vocabulary, postulates
  and theorems
• (but NOT the warm-up, examples, or cool-down.