Download Chapter 3.4 Polygons Day 1 .notebook

Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
DIRT
Identify the relation of the
angle pairs:
1) <1 and <9 ____________
2) <2 and <7 ____________
3) <7 and <11 _____________
4) <9 and <16 ____________
5) <1 and <4 ______________
6) <6 and <11______________
7)<9 and <11_______________
8) Find the value of x to prove l // m
55
l
x+25
m
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
3.4 The Polygon Angle­Sum Theorems
Objective: To classify polygons
To find the sums of the measures of the interior and exterior angles of polygons
M.2.B.
Performance Standard 3.6 DOK­1
Knowledge MA 3
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
Polygon­ A closed plane figure with at least 3 sides that are segments. The sides intersect only at their endpoints and no adjacent sides are collinear.
examples:
counter­example:
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
Polygons
# of sides
type
3
4
5
6
7
8
9
10
n
4
Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
Naming a polygon­ Start at any vertex and list vertices consecutively.
A
R
L
B
G
E
List the vertices:
List the sides:
List the angles:
Name: ALGEBR 5
Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
Concave: when any part of the diagonals fall on the outside of the polygon.
Hmmmmmm ... Can a triangle be convex? Concave??? Why??
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
Remember equiangular?? What about equilateral?
When a polygon is both equiangular AND equilateral, we call it REGULAR.
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
Classify the polygon. Use three words if possible.
Ex 1)
Ex 2)
Ex 3)
Ex 4)
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
Classify the polygon. Use three words if possible.
Ex 6)
Ex 5)
Ex 7)
70
70
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
Sketch the polygon if possible.
Ex 8) Regular hexagon
Ex 9) Equilateral right triangle
Ex 10) Concave equiangular qualdrilateral
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
Exploration: Triangles and polygons
Using the dot paper provided, work with your desk partner and sketch each polygon.
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
Fill out the chart on your paper.
Type of
polygon
# of sides
# of triangles
Sum of the interior angles
triangle
quadrilateral
pentagon
hexagon
heptagon
octagon
nonagon
decagon
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
What conjectures can you make about the relationship between the number of sides of a polygon and the sum of the interior angles (1st and 4th column)? (Hint: think about patterns)
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
Worksheet Guide for p147-150 1-10, 55, 71-73, 80-86
1. Is the figure a polygon?______ If not, why? ___________________________________________
2. Is the figure a polygon?______ If not, why? ___________________________________________
3. Is the figure a polygon?______ If not, why? ___________________________________________
4. Is the figure a polygon?______ If not, why? ___________________________________________
5. Name of polygon: ___________________
Sides: ___________________________
___________________________
Angles: __________________________
__________________________
7. Name of polygon: ___________________
Sides: ___________________________
___________________________
Angles: __________________________
__________________________
6. Name of polygon: ___________________
Sides: ___________________________
___________________________
Angles: __________________________
__________________________
8. Classify by sides: _______________
Convex or concave? _____________
9. Classify by sides: _______________
Convex or concave? _____________
10. Classify by sides: _______________
Convex or concave? _____________
55. Provide 4 sentences to describe the figure.
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
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Chapter 3.4 Polygons Day 1 .notebook
October 30, 2013
71. Work: ____________________
72. Work: ____________________
y= ____________________
x= ____________________
73. Work: ____________________
80. opposite rays: ________________________
81. two right angles: ______________________
82. two segments: _______________________
x= ____________________
83. an acute angle: _______________________
y= ____________________
84. an obtuse angle: ______________________
85. a straight angle: ______________________
86. a midpoint: _________________________
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