Answer:
-11 ≤ x ≤ 11
Explanation:
Let's get a couple of definitions out of the way
Domain (defn)
The domain of a function is the complete set of possible values of the independent variable(input values to the function). This means that for this set of values, the function value(output of the function) should be determinate.
Range (defn)
The range of a function is the complete set of all possible resulting values(outputs) of the function, after we have substituted the set of domain values
In this figure it is clear that the domain (set of possible values for the x variable) is between -11 and +11 inclusive
So domain is -11 ≤ x ≤ 11
The range (though not asked for) is the set of y values for this domain from minimum to maximum
From the graph, minimum y = 1 at x = 5. Maximum value is 8 (there are two maxima at x = -7 and x=11 but they are the same value)
Range is 1 ≤ y ≤ 8