QUADRILATERALS: An Online Treasure Hunt for 3rd Year
High School (Mathematics)
Authored by M. Soco
Introduction
Forms of all shapes and sizes abound in our environment. Quadrilaterials are one
such set of forms. The term quadrilaterals should not be new to you. You were
introduced to quadrilaterals in your elementary grades. In this activity, you
will review what you’ve learned and learn new things about quadrilaterals.
The “rules” of the activity are simple: Working in groups of three, answer the
questions below by reading the online resources listed. To access an online
resource, simply click on its URL or address. After answering all questions,
answer the Big Question.
Questions
 What is a quadrilateral? Give a NONexample of a quadrilateral (a shape
that is not a quadrilateral).
 Enumerate the five common types of quadrilateral.
 When can you say that a trapezoid is isosceles?
 Describe a parallelogram.
 How does a square differ from a rhombus?
 Describe the diagonals of a square.
 Identify the parallelogram with diagonals that are congruent but not
perpendicular.
 Which of the quadrilaterals have two pairs of congruent opposite angles?
Resources
Quadrilaterals: Definition of A Quadrilateral, Parallelograms
http://www.math.psu.edu/geom/koltsova/section10.html
Quadrilaterals
http://www.math.com/school/subject3/lessons/S3U2L3GL.html
Parallelogram and trapezoid
http://www.bymath.com/studyguide/geo/geo8.htm
Shapes: Quadrilaterals
http://www.icteachers.co.uk/children/sats/quadrilaterals.htm
Quadrilateral Family Tree
http://www.monroemontessori.com/Staffinfo/quadrilateral_family_tree.htm
Diagonals in Quadrilaterals
http://www.intermathga.gatech.edu/tweb/CPTM1/dhabeeb/diagonalsinaquad/diagonalsinaquad.htm
Trapezoid Conjecture
http://www.geom.uiuc.edu/~dwiggins/conj19.html
Quadrilaterals in Geometry
http://www.mste.uiuc.edu/m2t2/geometry/quadrilaterals/default.html
Rectangle
http://www.ezgeometry.com/class/class6/6.3.4/6.3.4.htm
The Big Question
A. Make a concept map showing how the different quadrilaterals and their
properties are related to each other.
B. In the table below, check the characteristics that are applicable to the
given quadrilaterals.
Characteristics 
Parallelogram 
Rectangle 
Rhombus 
Square 
Trapezoid 
Trapezium 
1. All sides are congruent 






2. Two pairs of opposite sides are congruent 






3. Two pairs of opposite sides are parallel 






4. All angles are right angles 






5. Two pairs of opposite angles are equal 






6. Diagonals are equal 






7. Pair of sides is parallel 






8. No sides are parallel 






