Answer: Range is [tex]y \ge 9[/tex]
Explanation:
The range of [tex]f(x) = \sqrt{x}[/tex] is [tex]y \ge 0[/tex]
In other words, it's the set of nonnegative real numbers.
We only focus on the y values. We go from y to y+9, which means we shift each (x,y) point 9 unit sup.
Since we shifted 9 units up, we add 9 to each y value and that effectively moves the lowest point in the range (0) up nine units.
So we go from [tex]y \ge 0[/tex] to [tex]y \ge 9[/tex]
If you need the range in interval notation, then you would write [tex][9, \infty)[/tex]. Note the square bracket next to the 9 so we include this as part of the range.