Question

rigid transformations in the sss proof
the sss proof used the rigid transformations illustrated here. which transformations are used?
rotation, then translation, then reflection
translation, then rotation, then reflection
rotation, then reflection, then translation
translation, then reflection, then rotation

Explanation:

First, we observe the orientation - change which is rotation. Then the position - change without orientation change is translation. Finally, the mirror - like change is reflection.

Answer:

rotation, then translation, then reflection