Labels

When you add a point to an expression line, you'll automatically have the option to add a label. When the point is hidden, the label will still be visible, allowing you to use that text as a title or to label any part of your graph.

Watch the video for an introduction to labels, and read on to learn more.

First, add a point to an expression line. Then, check Label. This will automatically display coordinates of the point on the graph paper.

To create a text label, check Label and then type in the text of your choice. The graph paper will automatically update.

To display only the label without the point, click the Point icon in the expression list.

To label a point or angle in the Geometry Tool, first select one from the graph paper. Then, click Label . By default, points are labeled with letters and angles with their measurement. You can also enter a text label.

To label a point with its coordinate automatically, use the token navigator to drag and drop the point’s token into the expression list. Then, check Label.

The Angle and Directed Angle tools automatically label the angle measurement. To change the label, select the angle on the graph paper, click Label, and then enter a new label. You can also change the angle’s label from the expression list.

On the graph paper, select the segment then click Label. Enter the label or toggle to Length to display the segment’s length. Segments that are labeled with a length are rounded to the nearest hundredth of a unit. In the expression list, you can measure segments with the length function.

Learn more about the Geometry Tool in Getting Started: Desmos Geometry.

Click and hold the Color icon to open the Options menu for a point. From there, you can show or hide the point and its label, make it draggable, and adjust properties like opacity, thickness, font size, position, and angle of the label.

In the Geometry Tool, you will need to drag a point token to the expression list to open the menu. Points created using the Point tool are automatically draggable, which removes the Clickable toggle.

If you define points, such as \(m\) and \(b\), in an expression line, you can type \(\mathbf{$\{m\}}\) and/or \(\mathbf{$\{b\}}\) as a point label. This will display the numerical values of \(m\) and \(b\) on the graph paper, and the label will automatically update as the value of \(m\) or \(b\) changes.

In this example, you can also label the point by typing \(\mathbf{y=$\{m\}x+$\{b\}}\) to display the equation of the line in slope-intercept form that updates as you drag the sliders.

You can also use a back tick (`) to format the label using math text. You can combine this with dynamic labels to display equations on the graph paper.

You can also use dynamic labels to display the area of a polygon in the Geometry Tool.

If you set a variable, such as \(a\), to the area, a point labeled with the expression \(\mathbf{$\{a\}}\) will display the area as it adjusts to the changing dimensions of the polygon.