Lets call the above set of points [tex]L[/tex].
The domain is between minimum and maximum of the x-coords points specified,
[tex]\mathrm{min}(L;x)=0[/tex]
[tex]\mathrm{max}(L;x)=7[/tex]
So domain is [tex]D_L=[\mathrm{min}(L;x),\mathrm{max}(L;x)]=[0,7][/tex].
The range is the same story but you look at y values,
[tex]\mathrm{min}(L;y)=-8[/tex]
[tex]\mathrm{max}(L;y)=8[/tex]
So range is [tex]R_L=[\mathrm{min}(L;y),\mathrm{max}(L;y)]=[-8,8][/tex].
Hope this helps :)