Relationships among Special Quadrilaterals

Lesson Summary

• There are complex relationships amongst parallelograms, rhombuses, rectangles and squares.

• The relationships between these shape classes are based on the properties these classes have.

• For example
    - all rectangles are parallelograms, because a rectangle has ALL the properties that a parallelogram has.
    - all squares are rectangles, because a square has ALL the properties that a rectangle has.
    - only some rectangles are rhombuses, because a rectangle has SOME of the properties that a rhombus has.