We now have a tool in the Graphics 2 window that presents the physical context of the problem and in which students can manipulate the cable path. The objects in the Graphics 2 window are mathematical (geometric), but most of what students might see as mathematical is in the Algebra view. We will use the **Graphics View** to present the results as a function curve.

1. Open the **Graphics View** by clicking the menu icon and then** View** > **Graphics**

2. Click in the Graphics window to ensure that the plotting will occur there

3. In the Input window input a point P that links the location along the shore information (x-coordinate, independent variable) to the total cost of the cable (y-coordinate, dependent variable) by:

- In the Input box type
**P=(variable name for distance along the shore, variable name for total cost) **

4. It is likely that you will not see point P on the graph in the Graphics window since the scale does not fit the context. Adjust the scale by:

- Right-click in the Graphics window and select
**Graphics ...**
- Set the
**x Min** and **x Max** to fit the distance along the shore segment, i.e. 0 - 3. It is better to use -0.5 to 3 to keep the y-axis in view
- Set the
** y Min** and** y Max **to fit the range in total costs, i.e. something like 340 - 400 representing $M

5. Drag the point where the cable comes ashore on Wolfe Island and observe the graph in the Graphics window. You should see point P moving

6. Trace the curve by:

- Move point P to the (0,#) position
- Right-click on P and click
**Trace On **
- Drag the point at which the cable comes ashore on Wolfe Island. You should see a curve traced out on the graph in the Graphics window
- Return point P to the (0,#) position and remove the trace by
**View** > **Refresh Views**

7. Improve the presentation of the curve tracing by:

- Hide the label for point P
- Right-click on the Graphics window and select
**Graphics ... **

- Add a label for the x-axis

- Have the x-axis **Cross at **350, i.e. cross the y-axis at 350

- Add a label for the y-axis

- Have the y-axis **Cross at** 0, i.e. cross the x-axis at 0

8. Re-trace the cost curve by repeating 6 above

Your GeoGebra applet should look something like the image below. If you are having difficulties you can click on the image and open a new tab with the applet.

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