Hi Peter,
2 ways to add markers.
Easy way is to right click on the graph, select format from the pop-up menu and then tick the Show markers checkbox for either/both X & Y axes. click OK to finish.
On the graph now you should have 2 small black squares (placeholders) on the selected axes.
select one of them and enter the numberr you need.
Slightly harder way is:
If you want to add a horizontal line to a simple X-Y plot, seletct the Y-axis function place holder type a ',' (Comma) which should give you a new placeholder that allows a second trace to be added to the plot.
In this place holder type a value (say 0.4) and for a simple graph it should show a secondary line.
To add a vertical line, the same procedure will work on the X-axis placeholder.
You may need to add aa second (matching) entry on the Y-axis , MathCad does its best but once you start adding multiple graphs onto one plot it can get confused.
E.g. the Y-axis place holder will contain "f(x),y" and the X-axis "x,0.4"
Hope this makes sense.
Andy
NB: it usually helps to add you work sheet so that we can try to understand where the specific sticking point is.
