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Reflection

Flip a figure across a mirror line — the only basic rigid transformation that reverses orientation.

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Reflection

A reflection across a line ℓ\ell maps each point to its mirror image, with ℓ\ell as the perpendicular bisector of the segment joining the point to its image.

MirrorRule
xx-axis(x,y)→(x,−y)(x, y) \to (x, -y)
yy-axis(x,y)→(−x,y)(x, y) \to (-x, y)
y=xy = x(x,y)→(y,x)(x, y) \to (y, x)
y=−xy = -x(x,y)→(−y,−x)(x, y) \to (-y, -x)

This interactive lesson covers the geometric definition, the coordinate rules, orientation reversal, and how two reflections compose into a translation or rotation.

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📌 Related Topics in Transformations and Congruence

Rigid TransformationsTriangle Congruence TheoremsTranslationRotation

❓ Frequently Asked Questions

What is Reflection?▾
Flip a figure across a mirror line — the only basic rigid transformation that reverses orientation.
How can I study Reflection effectively?▾
Start by reading the study notes and working through the examples on this page. Then use the flashcards to test your recall. Regular review and active practice are key to retention.
Is this Reflection study guide free?▾
Yes — all study notes, flashcards, and practice problems for Reflection on Study Mondo are free to access. No account is needed.
What course covers Reflection?▾
Reflection is part of the Geometry course on Study Mondo, specifically in the Transformations and Congruence section. You can explore the full course for more related topics and practice resources.