finding a question about constrained regression - had a side constraint $x \geq y^*z$

Question

I saw a question that asked about solving a non-negative least squares problem with $3$ unknowns, $(x,y,z)$. But there was an additional constraint, $x \geq y^*z$. Would appreciate getting the location on this. Thanks in advance.

Answer 1

Hint

If you turn the problem into an optimization problem, Occupy Gezi gave the solution and this could be the simplest.

Another way would be to set $x=y z + \lambda^2$ and to run the regression using $\lambda,y,z$ as tuning parameters.