1. **Problem Statement:** Given that ABCD is a parallelogram, determine which of the following statements are NOT true: - Diagonals are congruent in length - Diagonals bisect angles - Opposite sides are congruent - Opposite angles are supplementary - Opposite angles are congruent 2. **Recall properties of parallelograms:** - Opposite sides are congruent: $AB = CD$ and $BC = AD$ - Opposite angles are congruent: $\angle A = \angle C$ and $\angle B = \angle D$ - Diagonals bisect each other: $E$ is midpoint of both $AC$ and $BD$ - Diagonals are generally NOT congruent unless the parallelogram is a rectangle - Diagonals do NOT bisect the angles in a general parallelogram - Opposite angles are NOT supplementary; consecutive angles are supplementary 3. **Evaluate each statement:** - "Diagonals are congruent in length": FALSE in general parallelograms (only true in rectangles) - "Diagonals bisect angles": FALSE in general parallelograms (only true in rhombuses) - "Opposite sides are congruent": TRUE - "Opposite angles are supplementary": FALSE, opposite angles are congruent, consecutive angles are supplementary - "Opposite angles are congruent": TRUE 4. **Conclusion:** The statements that are NOT true are: - Diagonals are congruent in length - Diagonals bisect angles - Opposite angles are supplementary **Final answer:** The NOT true statements are the first, second, and fourth.