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The Find the reflection that maps a given figure to another exercise appears under the High school geometry Math Mission. This exercise practices reflection on the coordinate plane.

Types of Problems[]

There is one type of problem in this exercise:

  1. Use the reflection tool: This problem provides a coordinate plane and two images that are congruent. The student is asked to find the correct line that would be used to reflect the preimage into the image.
    Defrefi1

    Use the reflection tool

Strategies[]

Knowledge of the coordinate plane and geometric transformations, particularly reflections, are encouraged to ensure success on this exercise.

  1. A reflection line is needed to define the reflection, and two points determine a line.
  2. By connecting the endpoints of the images and preimages you can find lines perpendicular to the line of reflection

Real-life Applications[]

  1. Reflection is a size preserving transformation, so figures are kept congruent, but it reverses orientation.
  2. Reflections connect with perpendicularity and mirror reflection.