What geometry theorem is dynamically being illustrated below? [br](Feel free to move the white points anywhere you'd like!)
[color=#000000][b]SSS~ Theorem:[/b][/color][br]If 3 sides of one triangle are in proportion to 3 sides of another triangle, then the triangles are similar. [br](In the applet above, [color=#000000]k = the scale factor.[/color]) [br][br]Here's a more fundamental key question: [i][color=#980000]How does this applet informally illustrate these two triangles are always similar? [/color][/i]