Question 910633
{{{y=-x^2+9}}}  ....parabola opens down since variable {{{x^2}}} has negative sign


 {{{ graph( 600, 600, -10, 10, -10, 10, -x^2+9) }}} 


so, the vertex is at ({{{ 0 }}},{{{9}}})

axis of symmetry: vertical line at {{{x=0}}}, which is {{{y-axis}}}

roots: {{{x=-3}}} or {{{x=3}}}

domain: {all {{{x}}} element {{{R}}} }  (all real numbers)
 
range: { {{{y}}} element {{{R}}} : {{{y<=9}}} }