II. Create a square in Sketchpad.

1. Open Sketchpad.

2. Select the tool to create a segment.
Select the segment straightedge tool.
If the ray or line is selected, press the mouse over the straightedge tool until the three selections appear. Choose the straightedge.

3. Draw a segment.
Target the mouse on the document. Press the mouse button and drag until the segment is a comfortable length. Release the mouse button.

4. Select the Selection Arrow Tool.

5. Create the next point.
Move the anywhere on the document. Click the mouse in order to deselect the segment.
Select the right endpoint of the segment.
From the top menu, select Transform, Mark Center. The right endpoint will flare up. Note: You can also mark the endpoint by double clicking on the endpoint.

Select the left endpoint. From the top menu, select Transform, Rotate.

Select Rotate, 90 degrees. Now you have a third point.

6. Create the fourth point.
Similar to the steps above. Select the new point, the lower right point.
From the top menu, select Transform, Mark Center. The lower right endpoint will flare up. Note: You can also mark the endpoint by double clicking on the endpoint.
Select the right upper endpoint.
From the top menu, select Transform, Rotate, 90 degrees.

7. Complete the square.
-Select the straightedge tool. Point the mouse over the upper right endpoint and drag to the lower right endpoint.
- Point the mouse over the lower right endpoint and drag to the lower left endpoint.
- Point the mouse over the lower left endpoint and drag to the upper left endpoint.

III. Further Investigation.

1) What is the total number of interior degrees of the square?
2) Measure the length of one side of your square (highlight one side, then select “measure – length.) How would you calculate the perimeter of your square? The area?
3) What is a regular quadrilateral?