 How to Classify Quadrilaterals,
a selection of answers from the Dr. Math archives.
 Quadrilateral Classification: Definition of a Trapezoid
 What is the correct definition of a trapezoid, and why?
 Inclusive vs. Exclusive
Definitions
 My geometry teacher says that a square is not also a rhombus,
a rectangle, and a parallelogram. Please help!
 Inclusive and Exclusive Definitions
 Are squares rectangles? Are rectangles squares?
 The Six Quadrilaterals
 My daughter forgot her textbook and needs to know the
six types of quadrilaterals.
 Quadrilaterals
 What is 4sided and has no equal angles?
 Is a Square a Rectangle?
 Are squares rectangles? What is a pentagon?
 Is a Square a Rhombus?
 I've come across different definitions of a "rhombus" that make
it unclear whether a square is a rhombus.
 Describing a Rhombus
 What is a rhombus?
 Rhombus vs. Rhomboid
 What is the difference between a rhombus and a rhomboid?
 Proving Quadrilateral
is a Parallelogram
 We are having a problem with the idea of a quadrilateral having
one pair of opposite sides congruent and one pair of opposite angles
congruent.
 For definitions and diagrams, see:
 Quadrilateral Formulas
 Dr. Math Geometric Formulas FAQ
