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Proving Parallelograms

  • Parallelogram Theorems:
    • If both pairs of opposite sides of a quadrilateral are congruent, then the quadrilateral is a parallelogram
    • If both pairs of opposite angles of a quadrilateral are congruent, then the quadrilateral is a parallelogram
    • If the diagonals of a quadrilateral bisect each other, then the quadrilateral is a parallelogram
    • If one pair of opposite sides of a quadrilateral is both parallel and congruent, then the quadrilateral is a parallelogram
  • A quadrilateral is a parallelogram if:
    • Both pairs of opposite sides are parallel
    • Both pairs of opposite sides are congruent
    • Both pairs of opposite angles are congruent
    • Diagonals bisect each other
    • A pair of opposite sides is both parallel and congruent

Proving Parallelograms

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Mathematics: Geometry