Which of the following best completes the proof showing that ΔWXZ ~ ΔXYZ? Since segment XZ is perpendicular to segment WY, angles WZX and XZY are both right angles and congruent. The proportion _ shows the corresponding sides are proportional, so the triangles are similar by the SAS Similarity Postulate. 16 over 12 equals 9 over 12 16 over 12 equals 12 over 9 12 over 12 equals 16 over 9 12 over 16 equals 16 over 9