Illustrative Mathematics
Find the Missing Angle
This one activity requires young geometers to pull together information they are currently learning with things they have learned previously. Here they rely on understanding something about parallel lines, alternative interior angles,...
Discovery Education
Discovery Education: Web Math: Find Out Things About a Right Triangle
Gives basic info about a right triangle. Also students can substitute values for sides or angles in order to find missing values. The method for solving is then explained.
Math Is Fun
Math Is Fun: Solving Triangles
Find guidelines to help you "solve" triangles, which means finding the value of missing sides and angles. Provided are examples of six scenarios in which you can solve a triangle's missing measurements, as well as relevant equations,...