To edit the axes of a chart that you have inserted:
Double-click on the chart.
A grey border appears around the chart and the menu bar now contains commands for editing the objects in the chart.
Choose Format - Axis, then select the axis (or axes) that you would like to edit. A dialogue appears.
Select from the available sections and make the required changes (for example, select the Scale tab if you want to modify the scale of the axis).
Click OK. In your document, click outside the chart to exit chart editing mode.