Polygons and Its Parts

Polygons

• Poly (means many) & gon (side)

• the sides are straight lines

• none of the line segments can cross one another

• the shapes are closed

Multiple Choice

What is a polygon?

• A closed figure made up of straight lines segments

• A closed figure made up of curved edges

• An open figure made up of straight line segments

• A closed figure made up of crossed line segments.

Not a polygon

• Not a closed shape.

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• ​Not straight line segments.

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• ​Sides that intersect

Multiple Choice

Which one is a polygon?

Multiple Choice

Which one is NOT a polygon?

Multiple Choice

Which one is a polygon?

Whatever their shape, all polygons are made up of the same parts:

sides, vertices (connecting points), and angles (inside and outside the shape).

Multiple Choice

What is a vertex?

• The point where two waves meet

• The point where two sides meet

Multiple Choice

Convex or Concave?

• convex
• concave

Multiple Choice

Convex or Concave?

• convex
• concave

Multiple Choice

Which of the following is a convex polygon?

Multiple Choice

Which of the following is a concave polygon?

Multiple Choice

Is the figure a polygon? Is it convex or concave?

• Not a polygon, convex
• Polygon, convex
• Not a polygon
• Polygon, concave

Multiple Choice

Is the figure a polygon? Is it convex or concave?

• Not a polygon, convex
• Polygon, convex
• Not a polygon
• Polygon, concave

Polygons are named according to the number of sides and angles they have.

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For example: a triangle has three sides, a pentagon has five sides, a dodecagon has twelve sides.

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Multiple Choice

Name this polygon

• heptagon

• Pentagon

• hexagon

• quadrilateral

Multiple Choice

Name this polygon

• Pentagon

• hexagon

• heptagon

• octagon

Multiple Choice

Name this polygon

• Hexagon

• triangle

• Pentagon

• Octagon

Multiple Choice

How many sides are on a quadrilateral polygon?

• 4

• 5

• 6

• 8

Multiple Choice

What is the name of a polygon that has 12 sides?

• decagon

• dodecagon

• nonagon

• undecagon

Multiple Choice

Which of the following figures is a scalene triangle?

Multiple Choice

What is the name of the segment that connects two nonconsecutive vertices of a polygon?

• Angle

• Diagonal

• Side

• Vertices

Multiple Choice

What polygon has no diagonals?

• Decagon

• Nonagon

• Quadrilateral

• Triangle