## Geometry Applet: Triangle

If a Java interpreter is installed with your Web browser, you should see a tringle drawn on a base CD with a draggable vertex A. The draggable vertex is limited to a horizontal line so that all the triangles have the same area. I shall be increasing the canvas size to 700 by 500 for use on interactive whiteboards as draggable diagrams.

The animation uses the same Geometry Applet code by David Joyce as the parallelogram in the previous post. The geometry applet provides a series of classes that allow constructions, and you can build constructions by passing an array of elements to the Java applet. The applet tag code that produces the diagram above is reproduced below…

<applet code=Geometry archive=Geometry.zip width=400 height=300> <param name=background value="white"> </param><param name=title value="Triangles with same area..."> </param><param name=e[1] value="X;point;fixed;0,50;none;none"> </param><param name=e[2] value="Y;point;fixed;400,50;none;none"> </param><param name=e[3] value="Z;point;fixed;0,250;none;none"> </param><param name=e[4] value="W;point;fixed;400,250;none;none"> </param><param name=e[5] value="ZW;line;connect;Z,W;none;none;yellow"> </param><param name=e[6] value="A;point;lineSlider;X,Y,200,50;blue;red"> </param><param name=e[7] value="C;point;fixed;100,250;black;black"> </param><param name=e[8] value="D;point;fixed;300,250;black;black"> </param><param name=e[9] value="CD;line;connect;C,D"> </param><param name=e[10] value="CAD;polygon;triangle;C,A,D;none"> </param><param name=e[11] value="XY;line;connect;X,Y;none;yellow;yellow"> </param><param name=e[12] value="h;line;foot;A,C,D;red;red;green"> </param></applet>