What geometry theorem is being shown in action below? [br](Feel free to move the gray points anywhere you'd like!)
[color=#000000][b]Theorem:[br][/b][/color]The [color=#980000][b]medians[/b][/color] drawn to [color=#9900ff][b]both legs [/b][/color]of an isosceles triangle are [color=#980000][b]congruent.[/b][/color]