Things to Learn

  • Understand the definition of reflection and perform reflections across a line using a transparency.
  • Show that reflections share some of the same fundamental properties with translations (e.g., lines map to lines, angle- and distance-preserving motion).
  • See that reflections map parallel lines to parallel lines.
  • Explore that a line L is the bisector of the segment joining P to its reflected image P’ for the reflection across L and for every point P not on L.

Reflection of the plane about a line

Reflections of the World

Exercise and Practice

Final Reflection of the Day