Answer
Left : not a graph of a function
Right: a graph of a function,
domain [-3, 3], range: [-2, 3]
Work Step by Step
The left curve fails the Vertical Line Test
(the line $x=0$ intersects it three times).
It is not the graph of a function of x.
The curve on the right passes the Vertical Line Test,
so it is the graph of a function of x.
The domain is [-3, 3] and the range is [-2, 3]
