Trigonometry: Area of a non-right-angled triangle (1/2)absinC

This video teaches the area rule for non-right-angled triangles. I show a brief proof for the rule and then teach how to use it to find the area of a triangle or to find a missing side or angle when given the area. There are 4 worked examples of varying difficulty.

Intro and proof 00:00
How to find the area 02:44
How to find a side length 03:35
Example 1 05:06
Example 2 09:09