Rotational Reflectional symmetry practice

Symmetry

• Lines of Symmetry

• Rotational Symmetry

Rotational Symmetry

• When you rotate an object and it looks exactly the same.

• Order of rotation: the number of times a object looks the same as it is being rotated 360 degrees (in a circle).

• Magnitude of rotation: the angle of rotation in which the object looks the same as it goes around in a circle.

The shape shown is a REGULAR Hexagon.

We can do 360/6=60 to find that every 60 degree rotation works to show rotational symmetry

​**The shape looks the same each 60 degree rotation***

Rotational symmetry

Minimum Degree for Regular Polygons

• Square - 4 sides 90^o minimum rotation 360/4 = 90

• Hexagon - 6 sides 60^o minimum rotation 360/6 = 60

• Heptagon - 7 sides 51.4^o minimum rotation 360/7 = 51.4

Fill in the Blanks

What is the minimum degree of rotation to show rotational symmetry for a regular octagon(8 sided shape)? (Just type the number of the degree)

Fill in the Blanks

What is the minimum degree of rotation for a pentagon (5 sided shape)? (Just type the number of the degree)

Multiple Choice

Which of the the following angle of rotations would map the regular hexagon onto itself?

• 52°

• 108°

• 120°

• 305°

Multiple Choice

How many degrees would you have to rotate the shape around Z clockwise until AB would overlap with ED

• 60 Degrees

• 120 degrees

• It will never perfectly overlap

• 180 degrees

Multiple Choice

How many degrees would you have to rotate the regular pentagon until AB overlaps with CD

• 72

• 144

• Reflect it over EC

• 90

Lines of Symmetry

Cutting an object in half with a line so that it creates symmetric parts. (Folded perfectly)

Multiple Choice

How many lines of symmetry does this shape have?

• 1
• 2
• 3
• 4

Multiple Choice

• A

• B

• C

• D

Multiple Choice

Consider the shape being REFLECTED over the line AD. After this reflection, what segment will AB be overlapping with?

• AF

• FZ

• FE

• None

Multiple Choice

Consider the shape being REFLECTED over the line FC. After this reflection, what segment will BC be overlapping with?

• CD

• ED

• ZC

• None

Poll

How confident are you that you could do well on a readiness task over this material?

• I'm not feeling great about this yet

• I get some of it, but I need more practice before I'm confident

• Feeling pretty good

• I got this!