A rectangle is a quadrilateral with two pairs of parallel sides and four right angles.  A square is a rectangle with four equal sides.  To see where rectangles and squares fit into the world of quadrilaterals.

Contents of this section: Rectangles, Squares Puzzle: Area of Smaller Square Finsler-Hadwiger Theorem

Related pages in this website:

Quadrilaterals -- classification and explanation of the various types of quadrilateral 

Rectangle Perimeter -- Proof that a square has the smallest perimeter of any rectangle with a given area 

The webmaster and author of this Math Help site is Graeme McRae.