Remember: Regular Polygons are polygons with EQUAL SIDES AND ANGLES.
Equilateral Triangle
Number of Rotational Symmetries
How many times does an [b]EQUILATERAL TRIANGLE[/b] rotate onto itself until it is back to the beginning? Include the rotation 360°.
List Rotational Symmetries
Choose the list that includes all Rotational Symmetries for an [b]EQUILATERAL TRIANGLE.[/b]
Square
Number of Rotational Symmetries
How many times does a [b]SQUARE[/b] rotate onto itself until it is back to the beginning? Include the rotation 360°.
List Rotational Symmetries
Choose the list that includes all Rotational Symmetries for a [b]SQUARE.[/b]
Number of Rotational Symmetries
How many times does a [b]REGULAR PENTAGON[/b] rotate onto itself until it is back to the beginning? Include the rotation 360°.
5
List Rotational Symmetries
Choose the list that includes all Rotational Symmetries for a [b]REGULAR PENTAGON.[/b]
Point of Rotation
Where is the point of rotation in each of the applets above?
Center of the polygon
Noticing Patterns
What do you notice about the number of times a regular polygon will rotate onto itself? What relationship do you see?
The number of sides match the number of times a regular polygon will rotate onto itself.
Calculating Degrees of Rotational Symmetry
Given the number of sides of an object, and that each full rotation is 360 degrees, how could you determine each degree of rotation for any regular polygon?
360 divided by the number of sides = minimum degree of rotation. Then, add that number to itself over and over until you get to 360.
Image of a Regular Hexagon
This image does not move. Use what you have learned to answer the following questions.
Number of Rotational Symmetries
Based on the patterns you described above, how many times does a [b]REGULAR HEXAGON [/b]rotate onto itself until it is back to the beginning? Include the rotation 360°.
6
List Rotational Symmetries
Using the pattern/formula you described earlier, list all degrees of rotation that will carry a [b]REGULAR HEXAGON [/b]onto itself. (Only enter the numbers).
60, 120, 180, 240, 300, 360
Rotational symmetry of Non-regular polygons
What happens when we try to rotate a polygon onto itself that doesn't have equal sides and angles? Explore with a rectangle and trapezoid below.
Rectangle (non-regular polygon)
Number of Rotational Symmetries
How many times did the rectangle land onto itself?
2
List Rotational Symmetries
What degrees of rotation landed a rectangle back onto itself? (Only enter the numbers)
180. 360
Number of Rotational Symmetries
How many times did the trapezoid land onto itself?
1
List Rotational Symmetries
What degrees of rotation landed a trapezoid back onto itself? (Only enter the numbers)
360
Summarize
Summarize in at least 3 sentences what you learned from this discovery applet. Include words such as regular polygon, non-regular polygon, rotational symmetry, sides, degrees of rotation, etc.