Question 743647
{{{y= -5x^2}}}.....here you have parabola with vertex in ({{{0}}},{{{0}}}) and {{{a=-5}}} which means {{{a<0}}} and parabola opens downward


{{{ graph( 600, 600, -5, 5, -10, 10,-5x^2) }}}

so, 

the domain is {{{all}}} {{{real}}} {{{numbers}}}

*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \text{domain }\left{all\,x\,\in\,\mathbb{R}\\right}]

& range 

{{{all}}} {{{real}}} {{{numbers}}} {{{less}}} and {{{equal}}} to {{{zero}}}

*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \text{range }\left{all\,y\,\in\,\mathbb{R}\:\,y<=0\right}]