Final answer:
The sequence of rigid motions to map triangle XYZ onto triangle BCA could involve translations, rotations, and reflections, depending on the relative positions and orientations of the triangles.
Step-by-step explanation:
To find which sequence of rigid motions will map triangle XYZ onto triangle BCA, we would consider transformations such as translations, rotations, and reflections. Since the triangles are congruent, we could use a combination of these motions to superimpose one triangle onto the other. One possible sequence could be a translation that aligns one vertex of XYZ with the corresponding vertex of BCA, followed by a rotation around that vertex until the sides align, and finally, a reflection may be needed if the orientation of the triangles is different. Without a specific figure to reference, we cannot provide an exact sequence, but understanding these motions can help us determine the sequence for a given pair of congruent triangles.