Consider the square below:
Four different axes (or lines of symmetry) are shown.
You can prove this by printing this page and cutting out the squares and folding
along the dotted lines.
The square also has rotational symmetry. If you cut out
the square below and place it on a flat surface. Place a pen or pencil on the
point in the center of the square. If you rotate that square 90, 180, or 270
degrees clockwise or counterclockwise, the square will look exactly the same as
it did before you rotated it.
JavaSketchPad pages are provided for you to explore symmetry
with quadrilaterals and pentagons. Move the red points until the original
figure and the reflection image are superimposed (i.e., when they figure and
image are on top of each other). When you have accomplished this the reflection
line is now the axis or line of symmetry for the figure.