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Reflections Over Different Lines

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About This Diagram

This diagram shows reflections over three common lines: the x-axis, y-axis, and the line y = x. Click each button to see the animated reflection.

Reflection Rules

Line of Reflection Coordinate Rule
x-axis (x, y) → (x, -y)
y-axis (x, y) → (-x, y)
y = x (x, y) → (y, x)

Visual Elements

  • Red line: Line of reflection
  • Blue triangle: Pre-image
  • Green triangle: Image (reflected)
  • Purple dashed lines: Perpendicular segments
  • Small squares: Mark perpendicular intersections

Key Concepts

  • Each point and its image are equidistant from the line of reflection
  • The line of reflection is the perpendicular bisector of segments connecting corresponding points
  • Orientation reverses (clockwise ↔ counterclockwise)

Interaction

Click "x-axis", "y-axis", or "y = x" buttons to animate each reflection.

Learning Objectives

  • Understand reflection rules for common lines
  • Apply coordinate transformations for reflections

Bloom's Taxonomy Level

Understanding and Applying - Visualizing reflections.

Iframe Embed Code

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        height="422px"
        width="100%"
        scrolling="no"></iframe>