a function is one-to-one which means every x-value has exactly one y-value associated with it. So, write your points (-2,-1) (1,1) (2,-1) (3,2) (4,-2)
since my x values didn't repeat it is a function.
mathematically speaking, since the graph is one-to-one it is a function.
the domain are my x values listed in order from lowest to highest and my range is the same but with y values.
domain is [-2,1,2,3,4]
range is [-2,-1,1,2]