Question

Use the graph to determine the function's domain and range. Explain your answer.

Note: Assume that the graph continues past the screen shot.

Answer 1

The domain is defined as  all the possible x values. The graph extends to the left and to the right without bounds  so the domain is All Real Values of x.
It can also be written as   (-∞, ∞)  This is called interval notation.

Note that  the minimum value of f(x)  is -4  so the range is [-4, ∞).   (All real values of y equal to or greater than -4)