Overview
Important

Special cases of parallelograms are quadrilaterals that satisfy additional conditions beyond those of general parallelograms. The most common special cases are rectangles, squares, and rhomboids.

Important properties

  • A rectangle is a parallelogram with four right angles.

  • A square is a parallelogram with four right angles and four equal sides.

  • A rhomboid is a parallelogram with opposite sides equal and angles not right angles.

  • All rectangles and squares are parallelograms, but not all parallelograms are rectangles or squares.

  • Diagonals in rectangles and squares are equal in length; in rhomboids, they are not.