# Number Line

With the Number Line question type you can show intervals or evaluate intervals that students created.

*Figure: Displaying and creating intervals on a number line.*

There are tools to create bounded and unbounded intervals with closed or open boundaries. Drawing multiple intervals on the same line or stacked is also possible.

*Figure: Multiple stacked intervals in the same figure.*

## Evaluating intervals

Algebrakit can evaluate intervals created by students. Specify the correct solution in the Solution panel of the authoring tool. Intervals created in this panel will not be visible to students.

*Figure: Draw the correct solution in the Solution panel.*

## Settings

There are several settings to configure the number line. Most of these are self-explanatory.

*Figure: Settings for the Number Line.*

**Tolerance**: Indicates how accurately students must draw an interval. There is probably no need to change the default value.**Guidelines**: How many intervals can be stacked vertically? The maximum value is 7.**Regular Ticks**: Configure the large and short 'ticks', the vertical lines on the number line. Choose 0 to disable the display of ticks. You can also choose the number line altogether.**Custom Ticks**let you position ticks manually.