Solving Oblique Triangles

To solve an oblique triangle means to find the lengths of the unknown sides and the measures of unknown angles. If two angles are known, then the third angle can be determined simply by knowing that the sum of the three interior angles must equal 180°. Both the law of sines and the law of cosines are important tools for solving oblique triangles.

In the case of the SSS triangle, there is an option to show and compute the enclosed area of the triangle as an application of Heron's formula.

The Demonstration allows you to investigate the four categories of oblique triangles, create examples that can be "solved" manually with paper, pencil, and calculator, and then easily have the lengths and measures of unknown sides and angles be displayed for verification of the manual solutions. In the category SSA the visual will demonstrate why there are at times two possible triangles rather than just one.