[b]Background[/b][br]On the [i]GeoGebra [/i]page, there are three lines (red, blue, green) and three drag points (A,B,C).[br]Use the MOVE [icon]/images/ggb/toolbar/mode_move.png[/icon]tool to move the drag points as you try to construct the following [br]challenges.[br][br]In your responses to the questions with each Challenge:[br] Use color to identify the lines: red, blue, or green.[br] Use the notation ADC and BEC to identify the angles.[br][b][br]Challenge 1[/b][br]Organize the lines so that the red and blue lines are parallel.[br]How can you prove that they are parallel?[br][b][br]Challenge 2[/b][br]Organize the lines so that the green line is perpendicular to the red line but the green line is not [br]perpendicular to the blue line.[br]How can you prove your construction is correct?[br][b][br]Challenge 3[/b][br]Organize the lines so that the green line is perpendicular to the red line and the green line is also [br]perpendicular to the blue line.[br]How can you prove your construction is correct?[br]What can you say about the red and blue line?