DO NOW

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DO NOW

• Page 442
• Numbers 6-8
• Numbers 11 and 12

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Chapter 10Lesson 7

• Polygons and Tessellations
• Objective
• Classify polygons and determine which polygons
  can form a tessellation

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Polygon

• A simple, closed figure formed by three or more
  straight lines.

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Circle the polygons
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Pentagon
5 sides
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Hexagon
6 sides
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Heptagon7 sides
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Octagon8 sides
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Nonagon 9 sides
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Decagon10 sides
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Regular Polygon

• A polygon that has all sides congruent and all
  angles congruent.

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Name the regular polygons
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Name the regular polygon
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Name the regular polygon
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Name the regular polygon
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Name the regular polygon
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Determine whether the figure is a polygon. If it
is, classify the polygon and state whether it is
regular. If it is not a polygon, explain why.
Answer The figure is not a polygon since it has
a curved side.
Example 7-1a
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Determine whether the figure is a polygon. If it
is, classify the polygon and state whether it is
regular. If it is not a polygon, explain why.
Answer polygon, not regular
Example 7-1b
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Determine whether the figure is a polygon. If it
is, classify the polygon and state whether it is
regular. If it is not a polygon, explain why.
Answer This figure has 6 sides which are not
all of equal length. It is a hexagon that is
not regular.
Example 7-2a
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Determine whether the figure is a polygon. If it
is, classify the polygon and state whether it is
regular. If it is not a polygon, explain why.
Answer not a polygon, sides overlap
Example 7-2b
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QUILTING Emily is making a quilt using fabric
pieces shaped as equilateral triangles. Can
Emily tessellate the quilt with these fabric
pieces?
Answer Yes, they can be arranged in a way that
the angles where the vertices meet make 360?.
Example 7-4b
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Various other sided figures

• Sides Name
• 11 Undecagon,
• 13 Tridecagon,
• 14 Tetradecagon,
• 15 Pentadecagon,
• 16 Hexadecagon,
• 17 Heptadecagon,
• 18 Octadecagon,
• 19 Enneadecagon,
• 20 Icosagon
• 30 Triacontagon
• 40 Tetracontagon
• 50 Pentacontagon
• 60 Hexacontagon
• 70 Heptacontagon
• 80 Octacontagon
• 90 Enneacontagon
• 100 Hectogon,
• 1,000 Chiliagon

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