Theorems concerning quadrilateral properties (K-A)

• Proof: Opposite sides of a parallelogram (K-A)
• Proof: Diagonals of a parallelogram (K-A)
• Proof: The diagonals of a kite are perpendicular (K-A)
• Proof: Rhombus diagonals are perpendicular bisectors (K-A)
• Proof: Rhombus area (K-A)