Question

Theorem: The diagonals of a parallelogram bisect each other.

Kim is writing the proof of the theorem using two properties of a parallelogram as shown below.

• The opposite sides of a parallelogram are parallel.
• The opposite sides of a parallelogram are congruent.



Using the two given properties, Kim proved that triangle AGB is congruent to triangle CGD using the ASA Postulate.

What theorem can Kim use to prove that segment AG is congruent to segment CG, and that segment BG is congruent to segment DG to show that the diagonals bisect each other?