Where do you graph 0, -1 and -1, 0 on a the coordinate plane? Please help asap

[tex]\setlength{\unitlength}{1cm}\begin{picture}(0,0)\thicklines\put(0,0){\vector(1,0){4}}\put(0,0){\vector(-1,0){4}}\put(0,0){\vector(0,-1){4}}\put(0,0){\vector(0,1){4}}\put(0,-1){\circle*{0.5}}\put(-1,0){\circle*{0.5}}\end{picture}[/tex]
View it from web .