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Proof: Opposite angles of parallelogram congruent

Showing that opposite angles of a parallelogram are congruent

Quadrilaterals

Quadrilateral overview
Quadrilateral properties
Quadrilaterals: kites as a geometric shape
Quadrilaterals: find the type exercise
Proof: Opposite sides of parallelogram congruent
Proof: Diagonals of a parallelogram bisect each other
Proof: Opposite angles of parallelogram congruent
Proof: Rhombus diagonals are perpendicular bisectors
Proof: Rhombus area half product of diagonal length
Area of a parallelogram
Whether a special quadrilateral can exist
Rhombus diagonals

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This collection was created November 2014.