So I am struggling with understading Structural Causal Modelling. I have the following model
$$z=Nz$$ $$y=-z+Ny$$ $$x=2*y+3*z+Nx$$
I have the following variable values
$$Ny=0; Nz=0; Nx=0; z=5 $$
If i intervene the variable $y=7$ what is the result then?
From my own calculations i have come to the conclusion 20, but I am really not sure. Can anyone help me?