HW: pg.15 #5-18all - cbsd.org · HW: pg.16 #33-40 all Warm-Up Part 2 With a partner brainstorm ......
Transcript of HW: pg.15 #5-18all - cbsd.org · HW: pg.16 #33-40 all Warm-Up Part 2 With a partner brainstorm ......
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Warm UpTopic: Segment Bisectors Draw Both
In the diagram above, Y is the midpoint. 𝑋𝑌 = 4𝑥 + 2 𝑎𝑛𝑑 𝑋𝑍 = 28
𝑋𝑌 =
𝑋𝑍 = 𝑌𝑍 =
𝑥 =
In the diagram above 𝐴𝐵 = 2𝑥 − 2,𝐵𝐶 = 𝑥 + 9 𝑎𝑛𝑑 𝐴𝐶= 4x - 1
𝐴𝐵 =
𝐵𝐶 = 𝐴𝐶 =
𝑥 =
HW: pg.15 #5-18all
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HW: pg.16 #33-40 all
Warm-Up Part 2With a partner brainstorm everything you know about angles
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Today’s Agenda
▪ Learning Targets:– I can name angles and find their measures
– I can state and use the angle addition postulate
▪ Brainstorm Activity
▪ Notes: Section 1-4
▪ Classwork
▪ Homework
Section 1-4: Angles
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Angle
▪ The figure formed by two rays that have the same endpoint
▪ Rays: sides 𝐵𝐴 𝑎𝑛𝑑 𝐵𝐶– Common endpoint = vertex B
– Notation: ∠ 𝑜𝑟 ∡
A
B C
Naming Angles
▪ Need three letters or a number
B
Q D
C
1
2
With #: ∡ 1 , ∡ 2
With 3 Letters: ∡BQC , ∡DQC• The angle must go in the
middle
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Measuring Angles
▪ Degree: the unit for measuring angles
▪ 58°
▪ Postulate 3: Protractor Postulate–Gives a method/system for measuring
angles
Symbol
Classification for Angles
Acute
▪ Definition: between 0°and 90°
▪ Examples:
Create your own example
15 °
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Classification for Angles
Obtuse
▪ Definition: between 90°and 180°
▪ Examples:
Create your own example
165 °110 °
Classification for Angles
Right
▪ Definition: exactly 90°
▪ Examples:
⊓
Means right ∡
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Classification for Angles
Straight
▪ Definition: exactly 180°
▪ Examples:
Straight line
Postulate 4: Angle Addition Postulate
1.If point B lies in the interior of ∠𝐴𝑂𝐶, then
m ∠𝐴𝑂𝐵 +𝑚∠𝐵𝑂𝐶 = 𝑚∠𝐴𝑂𝐶
A
OC
B
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Postulate 4: Angle Addition Postulate
2. If ∠𝐴𝑂𝐶 is a straight line and B is any point not on 𝐴𝐶, then
m ∠𝐴𝑂𝐵 +𝑚∠𝐵𝑂𝐶 = 180
AO
C
B
Example 1
B
Q D
C
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Example 2 Calculate x
(4x+3)°(6x+7)°
Congruent Angles
▪ Angles that have the same measures
40
R
40
S
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Adjacent Angles
▪ Two angles in a plane that have a –Common endpoint (vertex)
–Common side
–But no common interior points (no overlap)
Bisector of an angle
▪ The ray that divides the angle into two congruent adjacent angles
A
BC
d𝐵𝑑 𝑏𝑖𝑠𝑒𝑐𝑡𝑠 ∠𝐴𝐵𝐶𝐵𝑑 is the bisector of ∠𝐴𝐵𝐶∠𝐴𝐵𝐶 is bisected by 𝐵𝑑
∠𝑨𝑩𝒅 ≅ ∠𝒅𝑩𝑪
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Example 1
Example 2
A
BC
B
8x-12
5x+9
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Find your partner below and sit together. Bring your book, paper and a calculator
Lauren & Madison
Shannon & Ryleigh
Kim & Chris A
Julia A & Gabriella
Sam B. & Clayton
Chris G. & Carolyn Nikita & Emily
Matt & Sam M. Jeremy & Erica
Ryan M & Ethan H.
James & Julia R.
Gary & MacKenzie
Gianna & Ethan A.
Dalton & Devon
Partner Practice Directions
▪ With your partner, you will both complete pg. 20 #1-16
▪ When you are finished, you will both bring your papers to me to check your work
▪ If there is extra time, begin working on the crossword puzzle
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Closure: You are the teacher
▪ I would like you to create two quiz questions and include their answers
▪ These questions must be from the material from today’s lesson
▪ You will email these two questions to [email protected]
▪ Please label the subject of the email as quizquestions_lastname_block #
▪ I will include some of these questions in the warm-up on Monday
Homework
▪ Complete pg. 21 #3-18 & pg. 22 #29-30
▪ Selfieometry picture/caption due Monday
▪ Quiz Monday–Section 1-2, 1-5, 1-3
▪ Test Wednesday