The following investigations are intended to help you understand how mathematicians go about testing ideas that they [i]think[/i] are true but which have not yet [i]proved[/i]. [br][br]As you work through the problem, think carefully about the ideas you formulate and the ways you test them. Geogebra has many tools to help you in this investigation. Write down your findings and ideas as you investigate.

What statements do you think might be true about any parallelogram?[br][br][list=1][*]Use the Geogebra tools to investigate parallelogram ABCD and test your ideas.[/*][*]Record all of your findings on your worksheet[/*][*]When finished with investigation #1, continue to investigation #2.[/*][/list][br][i]If you need to reset you diagram during the investigation, click the refresh button in the top right.[br][/i]

[b]Use the segment tool to draw diagonals AD and BC.[br][/b][br]What true statements can be made about the diagonals?[br][list=1][*]Use the Geogebra tools to investigate and test your ideas.[/*][*]Record all of your findings on your worksheet[/*][*]When finished with investigation #2, continue to investigation #3.[/*][/list][br][i]If you need to reset you diagram during the investigation, click the refresh button in the top right.[/i]

[br]What true statements can be made about rectangle ABCD?[br][list=1][*]Use the Geogebra tools to investigate and test your ideas.[/*][*]Record all of your findings on your worksheet[/*][/list][br][b]Next, use the segment tool to draw diagonals AC and BD.[br][/b][br]What true statements can be made about the diagonals?[br][list=1][*]Use the Geogebra tools to investigate and test your ideas.[/*][*]Record all of your findings on your worksheet[/*][/list][i][br]If you need to reset you diagram during the investigation, click the refresh button in the top right.[/i][i]If you need to reset you diagram during the investigation, click the refresh button in the top right.[/i]