Analyzing a Proof Click here to see a proof of the converse of the parallelogram angle theorem. As you read through the proof, look for how to complete the statements on the right. Complete the statements by choosing the correct answer from the drop-down menu. Are being used to get the equation in step 6. Are being used to get the equation in step 8. Are being used to get the equation in step 9. In step 14, "similar argument" means to draw segment and follow the same logic in steps 3-12.