Input X coordinate on graph and output Y coordinate?

[DreamcastDiego]

Good Afternoon,

I am trying to find a way to output the Y coordinated of a point of a graph when I input a X coordinate. Is there a function or formulae that would allow me to do this. I have tried using the 'TREND' function but my trendline does not fit perfectly to my graph line so it doesn't work. Here is what the graph looks like for reference:

Ideally, I would be able to type in excel an X value (distance to wall) and have three Y values (settlement) output, one for each line. For example, x = 1, y = 6.3, 7, 13.3.

Any help in this situation would be greatly appreciated! If there is another option for this that would work please tell me!

[#2]

@DreamcastDiego 

Could you attach a sample workbook (without sensitive data), or if that is not possible, make it available through OneDrive, Google Drive, Dropbox or similar? Thanks in advance.

[#3]

@Hans Vogelaar Sorry for the delay. Here is a worksheet with the data and graph I am trying to work with. You help is appreciated!

[#4 · Accepted solution]

@DreamcastDiego 

Thanks. The attached version uses linear interpolation. The X is in F30 and the results in F31:F33.

I left some helper formulas in G30:H33. If you wish, you can substitute them into the formulas in F31:F33.

[#5]

Thank you so much, this is exactly what I needed