Goals of the Unit

- understand important properties of symmetry
- recognize and describe symmetries of figures
- use tools to examine symmetries and transformations
- make figures with specified symmetries
- identify a basic design element that can be used with a transformation to replicate a given design
- perform symmetry transformations of figures, including reflections, translations, and rotations
- examine and describe the symmetries of a design made from a figure and its image(s) under a symmetry transformation
- give precise mathematical directions for performing reflections, rotations, and translations in terms of the effect of the transformation on points of the original figure
- draw conclusions about a figure in terms of the effect of the transformation on points of the original figure based on what symmetry or symmetries the figure has
- understand that figures with the same shape and size are congruent
- use symmetry transformations to explore whether two figures are congruent
- give examples of minimum sets of measures of angles and sides that will guarantee that two triangles are congruent
- use congruence of triangles to explore congruence of two quadrilaterals
- use symmetry and congruence to deduce properties of figures
- write coordinate rules for specifying the image of a point under particular transformations
- appreciate the power of transformational geometry in the real world
Vocabulary
angle of rotation reflection transformation
basic design element reflection symmetry translation
congruent rotation translation symmetry
congruent figures rotation symmetry
line reflection symmetry
line of symmetry tessellation
basic design element reflection symmetry translation
congruent rotation translation symmetry
congruent figures rotation symmetry
line reflection symmetry
line of symmetry tessellation