Just press "1", "2" or "3" at the same time you click to place a point of the triangle. The file does the rest.
A maths experiment-game. It's funny to make a triangle. The file show us the legth of its sides and its angles.
NOTE: use FIREFOX BROWSER or enable FLASH in your browser to play FLASH games. HTML5 games can be played in any browser. Download latest flash from adobe( http://www.adobe.com/go/getflashplayer )