Fitting equation system for triangular matrix

I am trying to fit a triangular matrix A to an equation system y = A*x,
where x and y are two vectors of the same size.

If A would could be just any rectangular matrix, the following would work:
x = rand(10,1); y = rand(10,1); # some random vectors
A = y/x;  # matrix such that y = A*x

However, I'd like A to be lower triangular, because the physics behind my
problem dictate this. The coefficients in A should be such that A solves y
= A*x in a least-squares sense. I suspect this is really a basic
linear-algebra question, but I am not sure. How do I do that in Octave?


----------
We are transitioning to a web based forum
for community help discussions at
https://octave.discourse.group/c/help