Concept Byte: Frieze Patterns

Use With Lesson 9-6

A frieze pattern is a design that repeats itself along a straight line. You can see frieze patterns in design trim. They often appear along the edges of buildings or as wallpaper borders of rooms. Every frieze pattern can be mapped onto itself by a translation.

Some frieze patterns can be mapped onto themselves by reflections.

  1. A frieze pattern consists of a series of a curve rising up to the top and falling back to the bottom, with a symmetrical petal shape below, and a teardrop shape on either side.
  2. A frieze pattern consists of a series of eight-pointed stars around eight-pointed stars.

Some frieze patterns have repeated rotational symmetry.

  1. A frieze pattern consists of a series of figures shaped like an L interlocked with an upside-down backwards L.
  2. A frieze pattern consists of a series of connected, X-shapes.

Some frieze patterns show glide reflections.

  1. A frieze pattern consists of a series of three leaves connected at the tips of their stems in the center, alternating one and two leaves on top.
  2. A pattern consists of a series of connected V shapes.

Exercises

For Exercises 1−4, refer to the frieze patterns above. You may find tracing paper helpful.

  1. For each frieze pattern, find a portion (as small as possible) that you could translate repeatedly to form the entire pattern.
  2. Which patterns show reflectional symmetry? Find their reflection lines.
  3. Which patterns show rotational symmetry? Find their centers of rotation.
  4. Which patterns show glide reflections? Find a glide translation and reflection line.

For each frieze pattern below, describe all transformations that map the pattern onto itself.

  1. A pattern consists of a series of T shapes connected by triangular shapes.
  2. A pattern consists of a series of intertwining arrow shapes, alternating pointing up and down.
  3. A pattern consists of a series of curves rising up then falling down to a circle then falling back down.
  4. A pattern consists of a series of U shapes opening right, with lines from the bottom of shape extending left into the opening of the previous.
  5. A pattern consists of a series of connected arrows pointing right.
  6. A pattern consists of a series of connected N shapes, sharing a side, alternating normal and backwards.

End ofPage 593

Table of Contents

Prentice Hall Geometry Chapter 1 Tools of Geometry Chapter 2 Reasoning and Proof Chapter 3 Parallel and Perpendicular Lines Chapter 4 Congruent Triangles Chapter 5 Relationships Within Triangles Chapter 6 Polygons and Quadrilaterals Chapter 7 Similarity Chapter 8 Right Triangles and Trigonometry Chapter 9 Transformations Chapter 10 Area Chapter 11 Surface Area and Volume Chapter 12 Circles Skills Handbook Reference Visual Glossary Selected Answers Index Acknowledgments