Module Overview
Quadrilaterals

a building with many geometric shapes

A quadrilateral is simply a four-sided polygon. In general, quadrilaterals may be classified as regular (having all sides congruent and all angles congruent) or non-regular (a variety of side lengths and angle measures). They may be convex (all interior angles less than 180 degrees) or concave (one or more interior angles greater than 180 degrees). In this topic, you will study five types of quadrilaterals – parallelograms, rectangles, squares, rhombuses and trapezoids. You will explore and apply the properties of each of these quadrilaterals and apply them to real world situations. You will find that there are some common characteristics among these four-sided figures.

Getting Started

Quadrilaterals Games Interactivity Getting started iconA quadrilateral has four sides, is two-dimensional, closed, and has straight sides. There are five types of quadrilaterals. Before you begin your exploration of quadrilaterals and their properties, see if you can correctly identify important vocabulary terms you will learn more about in this module. Click the player button to get started.

Key Vocabulary

Glossary iconTo view the definitions for these key vocabulary terms, visit the course glossary.

congruent
diagonal
parallel lines
parallelogram
polygon
quadrilateral
rectangle
rhombus
right angle
square
trapezoid