Answer
The given relation represents a function.
domain:
$(-\infty, 1]$
range:
$[-1, +\infty)$
Work Step by Step
The given graph includes the x-values that are less than or equal to 1.
Thus, the domain is $(-\infty, 1]$.
The given graph includes the y-values that are greater than or equal to $-1$
Thus, the range is $[-1, +\infty)$.
Note the all possible vertical lines that will pass through the graph will do so at exactly one point.
The graph passes the vertical line test; therefore, the given relation represents a function.