The graph below shows an office worker's annual salary:What are the domain and range of the function? Why are the x-values nonnegative?
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Okay, here we have this:
Considering that the domain refers to the possible values of x that can be substituted in the correspondence rule of a function. We can see in the function that the domain is [0, +∞) (because there is an arrow that indicates that it continues to increase).
And as the range is the set of numbers that depend on the substitution (tabulation) of the values that "x" can take. We can see that the range is [5000, +∞).
And the number of years is non-negative because the years that elapse are always counted forward, that is, they begin to count from zero.