
The graph is a function
Step-by-step explanation:
The domain are the x values of a function. They are the input of the function
From the graph, following the x axis:
The arrow on the line indicates it doesn't end.
As a result, it moves from negative infinity to positive infinity

Range are the y values of the function. They are the output of a function
From the graph, following the y axis:
the line starts from y = -3 towards the positive side of y axis.
Since there is an arrow on the line pointing upwards towards the y axis, it indicates positive infinity.

For it to be a function, the input will have only one output:
Each of the x values (input) gives only one y value (output)
The graph is a function