What is the reason for the third step in this proof?

Corresponding sides of congruent triangles are equal in length.

The diagonals of a rectangle bisect each other.

SSS criterion for congruence

Opposite sides of a parallelogram are congruent.

Question

What is the reason for the third step in this proof?

Corresponding sides of congruent triangles are equal in length.

The diagonals of a rectangle bisect each other.

SSS criterion for congruence

Opposite sides of a parallelogram are congruent.

directrix · Answer

@jwatts45  Please post the proof so that we can see the third step.

anonymous · Answer

Opposite sides of a parallelogram are congruent.