Gauss-Jordan and jit.la.uppertri

Hi all.
I want to make a 3D motion tracking thanks to two cameras and triangulations formulas.
Here’s my point: I don’t really know the way to deal with the 2 pairs of coordinates from the cameras to reach the 3d final point with x;y;z coodinates.

Is the the Delaunay’s triangulation the key ? Or the Gauss and Jordan matrixes ?
I have the feeling that the jit.la.uppertri could help me, but i need a start, because I’m pretty lost right now !

Has someone already dealt with that kind of stuffs ?
Thx all.

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