The given function is

The inverse function is

To get the inverse, we swap each x and y coordinate.
The rule is 
So that's why the point (0,1) becomes (1,0) for instance.
The real definition is worth a large deal of money so A
Answer:
y=x-3
Step-by-step explanation:
Graph y=x-5 and the point (1,-2). You want your slope to be the same for the lines to be parallel. The slope in the given equation is 1/1. Type into a graphing calculator y=x- and pick a number greater than negative five since the point (1,-2) is above the given line. Guess and checking reveals -3 to be the correct answer. Therefore, your answer is y=x-3.
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