Obtaining the slope from a chart's trend line

[eddyq]

On an XY (scatter) chart, I can make a trend line via right click on the line and select "Add trend line".

Are there formulas that will give me the left and right y values of the trend line?

[shg]

Welcome to the forum.

You can use LINEST to get the slope and intercept of the trend line, and then use formulas that use the min and max x values to get the y values for the endpoints.

[eddyq]

Thanks, I'll check into LINEST.

[castabya]

If the equation of the line is in y = mx + b, and you are displaying the equation already, you have what you need for the slope of the line. Just use arctan(m/ to determine the slope. Are you looking for the offsets normal to the theoretical line from there? I have an application where I am doing something similar, and use: cos(Ye-Ya) where Ye is the expected Y for a given X, and Ya is the actual Y. Hope this helps.

My issue is getting this offset line to graph in the scatter plot along with the existing chart. Any advice there?

[shg]

castabya,

I you have a question, please start your own thread.