Question

triangle abc is congruent to △abc by the hl theorem. what single rigid transformation maps △abc onto △abc? dilation reflection rotation translation

Explanation:

Step1: Recall rigid - transformation properties

Rigid transformations preserve shape and size. Dilation is not a rigid transformation as it changes the size.

Step2: Analyze the position of triangles

Observing the position of $\triangle ABC$ and $\triangle A'BC'$, we can see that they are mirror - images of each other with respect to line $BC$. A reflection is a transformation that flips a figure over a line.

Step3: Eliminate other options

Rotation turns a figure around a point and translation slides a figure without rotation or reflection. These do not match the transformation from $\triangle ABC$ to $\triangle A'BC'$.

Answer:

B. reflection