Trapezoid abcd is congruent to trapezoid a b c d which sequence of transformations could have been used to transform trapezoid abcd to produce trapezoid a b c d

If the trapeziods are congruent, then the trapezoid could have been translated, rotated or reflected across some axis. All of these forms of transformation move the object without altering the shape/size of the object.

Translated, Rotated or Reflected