Chapter 13

Properties of Triangles and Four-sided Figures

Chapter Introduction
Lesson 13.1 Classifying Triangles
Lesson 13.2 Measure of Angles of a Triangle
Lesson 13.3 Right, Isosceles, and Equilateral Triangles
Lesson 13.4 Triangle Inequalities
Lesson 13.5 Parallelogram, Rhombus, and Trapezoid
Critical Thinking Skills: Put on your thinking cap
Chapter Review
Chapter 13 Test Prep

KHAN ACADEMY

Chapter 13: Properties of Triangles and Four-Sided Figures

This section shows you how to classify shapes from triangles to quadrilaterals – properties and types.

http://www.khanacademy.org/math/cc-fourth-grade-math/cc-4th-geometry-topic/cc-4th-classifying-shapes/v/quadrilateral-overview

Chapter 13: Properties of Triangles and Four-Sided Figures (Quadrilaterals only)

This section of Khan Academy offers lessons on quadrilaterals only – properties and types of quadrilaterals.

http://www.khanacademy.org/math/cc-fifth-grade-math/cc-5th-geometry-topic/cc-5th-quadrilaterals/v/quadrilateral-overview

***************Three Dimensional Shapes

This section offers lessons on how we measure volume using unit cubes. It also shows you a lesson on volume of a rectangular prism or box.

http://www.khanacademy.org/math/cc-fifth-grade-math/cc-5th-measurement-topic/cc-5th-volume/v/how-we-measure-volume

WEBSITE SUPPORT

mathisfun.com – classifying triangles + interactive model

mathisfun.com – quadrangles interactive model

Khanacademy.com – triangle inequality theorem

***Additional Resources on Three Dimensional Shapes

learner.org – click on shape: interactive prisms and pyramids with various bases

education-portal.com – types of pyramids and more

mathisfun.com – click on shape: prismscylindersphere, cone

mathisfun.com – platonic solids (contains edges, faces, vertices, nets, and formulas for surface area and volume)