Graphs and charts

Use a Graph when the mathematics is the point: two curves such as y = x² − 2 and y = x, the points where they meet, a minimum, a segment between two points.

Use a Chart when you have data: a year of temperatures, measurements from a lab, results to compare. A chart can put two quantities with different units on one figure, one against the left axis and one against the right, and you can point out what matters with annotations.

Both are for reading and exploring, so there is nothing to answer. If students should plot or draw something themselves, use a Graph task instead.

For a graph:

1. In a worksheet, use the + between two items and choose Graph.

2. Click the pencil to open it. On the canvas, click to add a point and drag to move it. Right-click a point to Connect to… another point, Set label or Delete it.

3. Under Elements, use + Add curve and type a function of x, for example x^2 - 2, then click Set. + Add point, + Add line (a Line, Segment or Ray) and + Add path work the same way, and every element can have a label.

4. Under Axes, set the Axis range and choose the Axis markings: Grid, Ticks and Number labels.

5. Write a title under the figure and click the tick.

For a chart:

1. Use the + and choose Chart, then click the pencil. The chart editor opens.

2. Pick the Chart type: Line chart, Bar chart, Pie chart, Scatter plot, Histogram or Box plot.

3. On the Data tab, type the values into the table, paste a block from a spreadsheet, or use Import CSV. On a chart with axes, choose for each series whether it is Drawn against the Left axis or the Right axis.

4. On the Axes tab, name each axis and give its unit.

5. On the Annotations tab, use Add annotation to place A label, A reference line or A measurement, such as the span of the summer months.

6. Click Save, then Close.

Students see the finished figure in the worksheet. On a graph they can drag the grid to look beyond the starting view, as long as Allow viewers to pan is on under Axes; it is on by default. On a chart they can use View larger to open it full size, and Download this figure to keep it as a PNG or SVG.

Nothing they do is saved or graded.

• Label the points students will talk about, such as an intersection or a minimum, so everyone can refer to them by name.

• Use the right axis only for a second quantity with a different unit. Two series in the same unit belong on one axis.

• An annotation says what to notice. One or two per chart are enough.

• Under Appearance, Text size Large reads better on a projector, and Show the data as a table puts the numbers under the chart.