Math Is Fun
Math Is Fun: Triangle Identities
View examples of triangle identities, equations that are true for all triangles: Law of Sines, Law of Cosines, and Law of Tangents. Follow links to learn more about the purpose and examples of each identity.
University of Georgia
University of Georgia: Inter Math: Oblique
This site describes the concept of oblique, expressing both triangles and three dimensional solids. Be sure to use the links to related terms, everyday examples, challenging problems, more information, and the interactive check point...
Lawrence Hall of Science
The Math Page: Trigonometry: The Law of Sines
Work through an explanation of the law of sines, how it is used with an obtuse angle, and a proof of the law of sines. Great site for students studying trigonometry.
Wolfram Research
Wolfram Math World: Oblique Triangle
This page gives a single-sentence definition of an oblique triangle (one with no right angles.)