Question

which transformation is a rigid transformation?

Explanation:

Step1: Recall Rigid Transformation

A rigid transformation (isometry) preserves the shape and size (side lengths, angles) of a figure. Translations, rotations, reflections are rigid; dilations (scaling) are not.

Step2: Analyze Each Option

• First figure: Sides/angles seem changed (non - congruent), not rigid.
• Second figure: Triangle is stretched (scaled), so not rigid (dilation - changes size).
• Third figure: The triangles appear congruent (same side lengths, angles), likely a rotation/reflection/translation (rigid transformation) as shape and size are preserved.

Answer:

The transformation of the third set of triangles (with \(E', F', D'\) and \(E, F, D\)) is a rigid transformation. (Assuming the third option's figure shows congruent triangles, so the rigid transformation is the one where the pre - image and image are congruent, like the last set of triangles in the given options.)