I tried to graph $y = (2-z)^{1/2}$ and I got half of a paraboloid that appears upside down from the point of $z = 2$ for $y$ values greater than or equal to $0$.
However, when I tried this on Geogobra, it did not work. I would like to know if it is because Geogobra does not support such an equation or if there is something fundamentally incorrect with the equation.
Thank you in advance.