Dear forum members,

I am doing a physics project, which requires me to find a certain value via graphical means. I read in my teachers notes that to obtain the uncertainty for a graphically derived value, one has to plot the shallowest and steepest slope, and then subtract the value obtained from the best fit line from the values obtained from the shallowest and steepest lines. I did this, and I get two different values for the difference between the shallowest line and the best fit line and the steepest line and the best fit line. Hence, my question is, which one of these values should I indicate as the uncertainty?

All help is apprecaited.

Thank you.