SYMMETRY

Transformation Unit, Lesson 7

ARE PEOPLE SYMMETRIC? Check to see if you

are symmetric. Find a photograph of

yourself where you are looking straight ahead.

Hold a mirror perpendicular to the photo at the line of symmetry for your face.

How do you look?

Cutting the photo on the approximate line of symmetry, and duplicating each side of the face, produced the pictures you see here. (The tilt of the head accentuated these images.)

Doctors repair damaged human faces by reconstructing the symmetry plane of the former healthy face from the damaged asymmetrical patient's face.

ARE PEOPLE SYMMETRIC?

LINE SYMMETRY Nature displays

line symmetry in some of its most beautiful work.

The balanced arrangement of symmetry creates pleasing and attractive forms.

The white line is the line of symmetry.

LINE SYMMETRY

Many flowers possess line symmetry.

The biologist's term for line symmetry is "bilateral symmetry."

The white line is the line of symmetry.

LINE SYMMETRY

This drawing has two lines of symmetry, as shown by the white lines.

Mosaics and art work often demonstrate the concept of reflections and line symmetry.

LINE SYMMETRY

This butterfly caterpillar displays line symmetry.

The pink line is the line of symmetry.

LINE SYMMETRY Certain letters of the

alphabet and words possess line symmetry (such as the samples in the photo).

Notice that some letters possess vertical line symmetry, some possess horizontal line symmetry, and some possess BOTH vertical and horizontal line symmetry.

LINE SYMMETRY Certain

geometric figures possess line symmetry.

The figures in the photo are only a sampling of the geometric figures which possess symmetry.

ROTATIONAL SYMMETRY

Order 4 Order 2 Order 3Order 1(no rotational

symmetry)

Signs may possess rotational symmetry.

ROTATIONAL SYMMETRY

Order 2 Order 4 Order 8Order 1(no rotational

symmetry)

Designs and patterns may possess rotational symmetry.

ROTATIONAL SYMMETRY

Order 12 Order 5 Order 7 Order 5

Hubcaps may possess rotational symmetry (disregarding center logo).

ROTATIONAL SYMMETRYH      I      N      O      S      X     

Z

Letters may possess rotational symmetry.

The order may vary depending upon the style of the letter.For example, the letter O could have order 2

if the O is elongated or order infinite if the O is circular.

ROTATIONAL SYMMETRY Grid patterns may possess rotational

symmetry.

These each have a rotational symmetry of order 4.