Answer
See graph
Work Step by Step
We are given the function:
$f(x)=-4\sqrt{x-1}$
We start graphing with the basic function $a(x)=\sqrt x$.
We horizontally shift $a(x)$ one unit to the right to get $b(x)=\sqrt{x-1}$.
Then we vertically stretch $b(x)$ by a factor of 4 to get $c(x)=4\sqrt{x-1}$.
Finally we reflect $c(x)$ about the $x$-axis to get $f(x)=-4\sqrt{x-1}$.
We use 4 points: $(1,0),(2,-4),(5,-8)$.
