Input X coordinate on graph and output Y coordinate?

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!