CK-12 Foundation
Ck 12: Exterior Angles Theorem
[Free Registration/Login Required] Students explore the concept of the exterior angles theorem by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more...
CK-12 Foundation
Ck 12: Interactive Geometry: 4.4 Theorems About Triangles
Discover some theorems about triangles.