SEDL
The Timss Mathematics Segment: Geometry
This site explores the area of congruent triangles and how it is a difficult area to understand.
Texas Instruments
Texas Instruments: Try Angle?
In this activity, students investigate properties of triangles by randomly generating possible side lengths for triangles. They learn to determine if three line segments can form a triangle. They also learn to classify triangles as...
Ministry of Education and Universities of the Region of Murcia (Spain)
Ministerio De Educacion Y Ciencia: Demostraciones Del Teorema De Pitagoras
An interactive visual aid with a good explanation of the Pythagoras Theorem. In this unit five different demonstration will be given.
Mangahigh
Mangahigh: Shape: Right Angle in a Semi Circle Rule
Test your knowledge of the measurement of angles in a triangle.
Khan Academy
Khan Academy: Constructing Triangles
Given the lengths of two sides of a triangle, what can we say about the third side? Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Varsity Tutors
Varsity Tutors: Hotmath: The Pythagorean Theorem
Twenty problems cover various aspects of the Pythagorean Theorem. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the problem then click the "View Solution" button to check each...
Math Is Fun
Math Is Fun: Interactive Triangles
This is an excellent tool for students to explore how changes in the size of a triangle's sides or angles affect its appearance. Different types of triangles and angles are presented.
Oswego City School District
Regents Exam Prep Center: Congruence of Triangles
Congruent means, "same size, same shape." Find out more about this concept at this test prep site with real world examples and pictures. Hands-on classroom activity and lots of practice. Knowledge of basic algebra and geometry concepts...
Oswego City School District
Regents Exam Prep Center: Pythagorean Theorem
Who was Pythagoras and what is his theorem? Explore this concept and its relationship to the measurement of a right triangle in this test prep lesson plan. The instructional activity includes an interactive worksheet where students...
Oswego City School District
Regents Exam Prep Center: Pythagorean Theorem
Material to supplement introductory instruction on the Pythagorean Theorem. A very simple look at its use in geometry, a multiple-choice quiz through which students can test themselves and check their answers, and a teacher resource...
Math Is Fun
Math Is Fun: Pythagoras' Theorem
This resource investigates the Pythagorean Theorem. Includes animations, examples, proofs, and links to problems and activities.
Math Planet
Math Planet: Pre Algebra: Triangles
Learn about the types of triangles by taking a look at an example and a video lesson.
Khan Academy
Khan Academy: Right Triangle Side Lengths
Use the Pythagorean Theorem to determine if the given side lengths could form a right triangle, i.e., which set forms a Pythagorean triple. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a...
BBC
Bbc: Pythagoras' Theorem
You can pick up some valuable pointers on how to apply the Pythagorean Theorem here. When you finish working your way through the pages you can take an on-line "Test Bite," and check your understanding.
TED Talks
Ted: Ted Ed: How Many Ways Are There to Prove the Pythagorean Theorem?
Betty Fei details these three famous Pythagorean theorem proofs.
Illustrative Mathematics
Illustrative Mathematics: 8.g Converse of the Pythagorean Theorem
This task asks students to explain what the Pythagorean Theorem and its converse are, how the converse works, and why it is true. Aligns with 8.G.B.6.
Math Open Reference
Math Open Reference: Triangles
A complete reference guide to types of triangles and triangle perimeter and area. It provides definitions and interactive animated activities that enhance further explanation.
CK-12 Foundation
Ck 12: Converse of the Pythagorean Theorem
[Free Registration/Login may be required to access all resource tools.] Learn about the converse of the Pythagorean Theorem and some of its applications. Also explains how to identify acute and obutse triangles through the use of the...
CK-12 Foundation
Ck 12: Geometry: Pythagorean Theorem and Pythagorean Triples
[Free Registration/Login may be required to access all resource tools.] Apply the Pythagorean Theorem and its converse. Includes videos, exercises, links to interactive activities, etc.
CK-12 Foundation
Ck 12: Flex Book: Pythagorean Theorem
[Free Registration/Login may be required to access all resource tools.] Learning module that introduces students to the Pythagorean Theorem. Topics include history, applications, and proofs related to this geometry concept.
CK-12 Foundation
Ck 12: Geometry: Pythagorean Theorem Study Guide
[Free Registration/Login may be required to access all resource tools.] This study guide is an overview of the Pythagorean theorem and its converse, Pythagorean triples, and proving the distance formula.
Education Place
Houghton Mifflin: Eduplace: What Is It? Pythagorean Theorem
This is a great place for information on the Pythagorean Theorem. Three other sections (tabs at the top) are available, including tips, students' questions, and lesson ideas.
Other
Gobierno De Navarra: Teorema De Pitagoras
Interactive figures to learn about the Pythagorean Theorem.
Common Core Sheets
Common Core Sheets: Geometry 8.g.7 Worksheets: Using Pythagorean Theorem
Worksheets provide practice using the Pythagorean Theorem and answer keys are provided. You can even create your own worksheet or flashcards.