CK-12 Foundation
Ck 12: Interactive Geometry: 1.7 the Pythagorean Theorem
Explore and discover the Pythagorean theorem.
Math Planet
Math Planet: Geometry: Converse of the Pythagorean Theorem and Special Triangles
The converse of the Pythagorean Theorem is examined through examples and a video lesson. [1:04]
CK-12 Foundation
Ck 12: Interactive Geometry: 10.2 Equations of Circles
Derive the equation of a circle with the help of the Pythagorean Theorem.
CK-12 Foundation
Ck 12: Interactive Geometry: 6.6 Theorems Involving Similarity
Learn the many theorems about triangles that you can prove using similar triangles.
Mathigon
Mathigon: Geometry: Triangles and Trigonometry: Pythagoras' Theorem
Pythagoras' Theorem: In any right-angled triangle, the square of the length of the hypotenuse (the side that lies opposite the right angle) is equal to the sum of the squares of the other two sides. (A+B=C)
CK-12 Foundation
Ck 12: Interactive Geometry: 6.7 Applications of Similar Triangles
Learn how similar triangles have congruent corresponding angles and proportional corresponding sides.
CK-12 Foundation
Ck 12: Interactive Geometry: 7.8 Triangles in Applied Problems
Explore some problems you can solve with your knowledge of triangles and trigonometry.
CK-12 Foundation
Ck 12: Interactive Geometry: 7.7 Law of Cosines
Learn how the Law of Cosines uses the measure of angle C to provide an equation that relates the three sides of the triangle with angle C.