Answer
$f(x)=9-\sqrt{-x}$
Work Step by Step
Since the shape of the graph is a $f(x) = \sqrt x$ we will start with that function:
$f(x)=\sqrt x$
The first transformation is 9 units down. Remember that shifts up or down are added to the right side of the equation. Up is positive and down is negative.
$f(x)=\sqrt{x}-9$
The reflection across the x-axis means multiply the right side by -1
$f(x)=9-\sqrt{x}$
The reflection across the y-axis means change the sign of the x on the right side.
$f(x)=9-\sqrt{-x}$
