It is a supplementary angle. D because the add up to 180.
ANSWER

EXPLANATION
To find a positive angle that is coterminal with

We add multiples of 2π until we get a positive angle that is less than one revolution,
We add to obtain,

This simplifies to,

This is the first positive angle that is coterminal with

and is less than one revolution.
Answer: Choice D) 
The steps to finding the inverse will have us swap x and y. Afterward, we solve for y

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Extra info:
The inverse relation is not a function because of the plus minus. For instance, plugging x = 4 into
leads to y = -3 and y = 3 simultaneously. You would have to apply a domain restriction on
to make it a one-to-one function, to make the inverse a function. One possible domain restriction is
which would lead to the inverse function 