Excel 2007 : Automatically Calculating the intercept of a trendline.

Morning everyone,

I'm sure this must have been asked before but I'bve searched and I can't find an easy solution!

I want to set up a spreadsheet which automatically calculates the interception on the x axis of a (linear) trend line on a graph (created by the user inputting three data points).

I could obviously work it out using the trendline formula for each data set but I want it to be automatic so anyone can enter three values and get an intercept point. Is there a way I can display the trendline forumla in a cell so that I can solve it for y = 0?

I have attached an example workbook as hopefully this explains it better!

Thanks in advance,

Alice