[i][b]The diagram below is via René Descartes' 1637 La Géométrie. [/b][/i] See [url]www.jonathancrabtree.com/1600s/1637-RDESCARTES_Extract_The_Geometry.pdf[/url] DRAG [b]x[/b] left or right with your mouse. MOVE IMAGE > Hold Shift and move the diagram on the screen with your mouse. ZOOM IMAGE > Hold Shift and zoom in and out with your mouse wheel. Reset the Applet to the default by clicking the icon top right. [color=#0a971e][b]Line segments are proportional to the real numbers they can represent.[/b][/color] For a fun applet showing [b]multiplication [/b]via [b]circles[/b], goto [url]http://bit.ly/Multiplication_with_a_Circle[/url] For a fun applet showing [b]multiplication [/b]via [b]triangles[/b], goto [url]http://bit.ly/Multiplication_with_Triangles[/url] For a fun applet showing [b]division [/b]via [b]circles[/b], goto [url]http://bit.ly/Division_with_a_Circle[/url] [i][b]So have fun![/b][/i] Jonathan Crabtree [url]www.jonathancrabtree.com/mathematics[/url] [url]www.linkedin.com/in/jonathancrabtree[/url] P.S. Goto [url]http://bit.ly/Proportional_Co-Variation[/url] to learn more about [i][b]Proportional Co-Variation[/b][/i].