Hi Greg,

To indicate the intersection point on a two-line graph, you can follow these steps:

1. Click on the chart to select it.
2. Click on the "Insert" tab in the ribbon at the top of the screen.
3. Click on the "Shapes" button in the "Illustrations" group.
4. Choose the arrow shape you want to use and draw it on the chart by clicking and dragging.
5. Click on the arrow to select it.
6. Click on the "Format" tab in the ribbon.
7. In the "Shape Styles" group, click on the "Shape Fill" button and choose "No Fill".
8. In the "Shape Styles" group, click on the "Shape Outline" button and choose a color for the arrow.
9. Click on the arrow again to select it.
10. Right-click on the arrow and choose "Format Shape" from the context menu.
11. In the "Format Shape" pane, click on the "Size & Properties" tab.
12. In the "Size & Properties" tab, under "Properties", set the "Lock aspect ratio" option to "Off".
13. In the "Size & Properties" tab, under "Size", set the "Width" and "Height" to the same value (e.g. 1 cm).
14. Click on the "Close" button to close the "Format Shape" pane.
15. Click on the arrow again to select it.
16. Click on the "Layout Options" button that appears next to the arrow.
17. Choose "More Layout Options" from the context menu.
18. In the "Format Shape" pane that appears, click on the "Text Box" tab.
19. Under "Text Box", choose "Do not Autofit" and set the "Margins" to "0 cm".
20. Click on the "Close" button to close the "Format Shape" pane.
21. Click on the arrow again to select it.
22. Click on the "Format" tab in the ribbon.
23. In the "Shape Styles" group, click on the "Shape Effects" button and choose "Glow" or "Shadow" to make the arrow stand out more.
24. Click on the arrow again to select it.
25. Click on the "Formula Bar" at the top of the screen.
26. In the Formula Bar, type "=" and click on the cell that contains the x-coordinate of the intersection point.
27. Type "," and click on the cell that contains the y-coordinate of the intersection point.
28. Press Enter to confirm the formula.
29. Move the arrow to the intersection point by clicking and dragging it.
30. Resize the arrow if necessary by clicking and dragging its handles.
31. The arrow and text box will automatically move to a new intersection as you change the numbers around.