Answer:
You must know the shape of the graph y = x². Its chart is in the form of an upward parabola. The shape of the graph y = -x² is the same except that it is downward. Finally, to draw the shape of the graph y = -x² + 9, we need to move the previously mentioned graph 9 units upwards.
The formula for the vertex length of a parabolic chart is as follows: x= -b/(2a) b=0 , a= 1 → x= 0, y=-(0)²+9=9
vertex: (0,9)