Answer
See graph
Work Step by Step
$$x=-y^2+6y$$
$$-x=y^2+6y$$
Complete the square.
$$-x+9=y^2+6y+9$$
$$-x+9=(y+3)^2$$
$$x=-(y+3)^2+9$$
This is a parabola with vertex (9,3).
Substitute 0 for x.
$$0=-(y+3)^2+9$$
$$-9=-(y+3)^2$$
$$9=(y+3)^2$$
$$y+3=3$$
$$y=0$$
$$y+3=-3$$
$$y=6$$
$$(0,0)$$
$$(0,6)$$
Plot these points and connect with a smooth curve.
