What geometry definition is dynamically being illustrated in the applet below? (Feel free to move any of the BIG WHITE VERTICES of either triangle around at any time.)
[b]Definition of CONGRUENT FIGURES: [/b][br][br]2 figures are said to be CONGRUENT if and only if one can be mapped onto the other using any 1 (or composition of 2 or more) isometries (geometric transformations that preserve distance.)