A7. The "Line" tool
Draw a line and name it "r"
The lines have no beginning or end, but GeoGebra can only draw them in the Graphics View using two points to define the line.
1st. Select the "Line" tool 
.
2nd. Click twice in the Graphics View (the line and both points appear).
3rd. Name the line you have just drawn "r".
You can also create two points with the "Point" tool 
, then activate the "Line" tool and click on both points. Try to drag the points and the line with the mouse.
The two curved arrows located in the upper right corner of the Graphics View allow you to reset the activity.
If the activity is correct, you will get 10 points automatically.
.
2nd. Click twice in the Graphics View (the line and both points appear).
3rd. Name the line you have just drawn "r".
You can also create two points with the "Point" tool , then activate the "Line" tool and click on both points. Try to drag the points and the line with the mouse.
The two curved arrows located in the upper right corner of the Graphics View allow you to reset the activity.
If the activity is correct, you will get 10 points automatically.