Sophia Learning
Sophia: Two Lines Tangent to a Circle: Lesson 2
This lesson will present how if two segments from the same point outside a circle are tangent to a circle, then they are congruent. It is 2 of 5 in the series titled "Two Lines Tangent to a Circle."
Shmoop University
Shmoop: Attributes of Circles
This video explains circumference, radius and diameter in an appealing way for students to understand.
Expansion Learning
Expansion Learning: Basic Shapes (Part One)
Video provides students with an explanation of the basic shapes of square, rectangle, triangle, and circle.
Mocomi & Anibrain Digital Technologies
Mocomi: Who Discovered Pi?
Learn about Archimedes and the discovery of Pi.