Symmetry Rotation Reflection

Re-cap… What type of transformations are there? What happens to the shape in a translation?

What do you think symmetry is?

Symmetry

What is a line of symmetry? A line on which a figure can be folded so that both sides match

To be a line of symmetry, the shape must have two halves that match exactly. When you trace a heart onto a piece of folded paper, and then cut it out, the two half hearts make a whole heart. The two halves are symmetrical.

Which of these flags have a line of symmetry? United States of America Canada No Maryland England No

What about these math symbols? Do they have symmetry? + - Yes Yes - x Yes Yes

How many lines of symmetry to these regular polygons have? 5 4 3 Do you see a pattern? 6 8

A B C D E FG H I J K L M N O P Q R S T U V W X Y Z MINDS ON: You can look to see if your name has symmetrical letters in it too! Write you name on paper to see how many lines on symmetry it has. A B C D E FG H I J K L M N O P Q R S T U V W X Y Z Infinite number

The action of turning a figure around a point or a vertex. Rotation (Turn) The action of turning a figure around a point or a vertex.

Turning a figure around a point or a vertex Rotation

Rotations can occur clockwise or counter clockwise

If a rotated an object a half turn, how many degrees do you think that If a rotated an object a quarter turn, how many degrees do you think that Is? If a rotated an object a half turn, how many degrees do you think that Is?

Trace the triangle in the top quadrant, rotate the object by 90 degrees clockwise and trace it again. Reposition the triangle in same place but in the second quadrant, rotate the object by 180 degrees clockwise and trace it again. Trace the triangle in the third quadrant, rotate the object by 90 degrees counter clockwise and trace it again. Reposition the triangle in same place but in the fourth quadrant, rotate the object by 180 degrees counter clockwise and trace it again.

The result of a figure flipped over a line. Reflection (flip) The result of a figure flipped over a line.

Reflection Click on this trapezoid to see reflection. The result of a figure flipped over a line.

Draw a line of symmetry in each of the 4 quadrants Draw the following shapes in each of quadrants Draw it’s reflection on the other side of the lines

Which shapes show reflection, translation, or rotation?