This could be a graph of $\displaystyle{f{{\left({x}\right)}}}=-{4}-\sqrt{{x}}\usepackage{cmbright}\Huge\$ . When you subtract a number outside the radical, the graph does move down from the graph of $\displaystyle\sqrt{{x}}\usepackage{cmbright}\Huge\$ . However, that does not affect the direction in which the graph goes.