Hello guys,
I encounter such this plot (attached) in the engineering books, but don't know which software the authors used. It is not only about the plot itself because plotting observed X-Y series is not difficult, but I mean how can they use the software to find exactly the coordinates of the interceptions? How can they project vertically or horizontally from a point? And how can they mark or draw whatever they want on the graph? I don't think Excel can do it.
Looking forward to your answers. Thank you!