Find intersection between to lines

New Contributor


I would like to find the point of intersection between to lines in excel. The blue dots are from column D and E and the orange is from column F and G. i have a lot of data and saw another way on the community on how to do it but i cant figure it out in my excel sheet. I am using excel on mac. 



1 Reply

I cannot read the image.  It is too small; and it becomes blurry when I zoom.  It is always better to attach an actual Excel file.


You ask about the intersection of two "lines".  Usually, the word "line" means a straight line.  But to my tired eyes, the blue curve does not appear to be straight.  Am I right?


If yes, would a linear approximation (trendline) of the blue curve be sufficient for your purposes?


If the mathematical formulas for the two (straight) lines are y1 = a1*x + b1 (orange) and y2 = a2*x + b2 (blue), where a1, a2, b1 and b2 are constants and y1 and y2 are names (like "x"), not cell references, they intersect at:


x = (b2 - b1) / (a1 - a2)

y = a1*x + b1


If you cannot translate the mathematics into Excel formulas for your worksheet, then again, it would behoove you to attach the Excel file.