Theorems concerning quadrilateral properties (K-A)

Proof: Diagonals of a parallelogram (K-A)

Proof: Opposite angles of a parallelogram (K-A)

Proof: Opposite sides of a parallelogram (K-A)

Proof: Rhombus area (K-A)

Proof: Rhombus diagonals are perpendicular bisectors (K-A)

Proof: The diagonals of a kite are perpendicular (K-A)