When you need to draw a graph requiring independent scaling of the axes, select File / New Graph.
- Draw your graph.
- Click an axis - the axis will be highlighted and a circular handle appears.
- Slide the handle up and down the axis with your mouse.
Note: Many of the geometry drawing, constraint and construction tools are unavailable (grayed out) in the Graphing mode for obvious reasons related to the independent scaling of the axes. And you cannot copy and paste between geometry and graph documents.