Question 408883


A common type of proof involves proving that a quadrilateral is a parallelogram. If any of the 5 conditions below are met, then the quadrilateral must be a parallelogram. 

    1) If a quadrilateral has one pair of sides that are both parallel and congruent, then the quadrilateral is a parallelogram.

   2) If a the opposite sides of a quadrilateral are congruent, then then quadrilateral is a parallelogram.

    3) Opposites sides are parallel.

    4) Opposite angles are congruent

  5) Diagonals bisect each other.

so, plot your vertices and see if they meet any of criteria above