Measurement- Polygons
Topic: Polygons
What are polygons?
A polygon is a flat figure that is made up of straight lines and is enclosed.
Note that if the polygon is:
- Flat – this means it’s a plane figure or two-dimensional
- Straight lines – these are called segments in geometry
- Enclosed – all the lines fit end-to-end and form a figure with no openings.
To demonstrate what we mean by enclosed and not enclosed look at the diagrams below.
These polygons are not enclosed:
These polygons are enclosed:
Types of Polygons
Here is a list of polygon names depending on the number of sides they have.
- 3 sides – Triangle
- 4 sides – Quadrilateral
- 5 sides – Pentagon
- 6 sides – Hexagon
- 7 sides – Heptagon
- 8 sides – Octagon
- 9 sides – Nonagon
- 10 sides – Decagon
Simple and Complex Polygons
Simple polygon the lines do NOT intersect while complex polygon lines intersect.
Examples:
Complex |
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Regular Polygons
Regular polygon have lines that are all the same length and it also has all the same angles.
Examples:
Regular:
Not regular:
Watch the video below: