Parallelograms – Properties  

A parallelogram is a special type of a polygon. it is a quadrilateral with both pair of opposite sides are parallel.

Properties

1. Opposite sides are equal.

      Opposite sides, AB = CD and AC = BD

2. Opposite angles are equal.

     Opposite angles are ∠A = ∠D and ∠B = ∠C

 3. Diagonals bisect each other.

Diagonals are AD and BC bisect each other at the point O.

 4. Consecutive angles are supplementary.

Consecutive angles are ∠A +∠C = 180º, and 

∠B +∠D = 180º

 5. If one angle is right then all angles are right.

 6. Each diagonal of a parallelogram separates it into two congruent triangles.

7. Diagonal AD separate it into two congruent triangles, △ADC and △ADB,

8. Diagonal BC separate it into two congruent triangles, △BDC and △BAC.