The domain of a function is the set of all values of x that satisfies the function. On the graph, it is between the minimum value of x on the left and the maximum value of x on the right.
Looking at the graph, it extends infinitely to the left. It moves towards x = 7 but never touches it. This means that there is a vertical asymptote at x = 7. It extends towards infinity on the right. Thus, the domain is
Domain = (-∞, 7) U (7,∞)
The range is the set of all values of y that satisfy the function. It extends from negative infinity at the bottom to y = 0 but never touches it. It extends from this point towards positive infinity at the top. Thus,
Range = (-∞, 0) U (0,∞)