For the function w, w (9) = - 7, and w (-7) = 9. If y=w (x), what is the value of y when x=-7?

That question is already solved, here is the proof:

w (-7) = 9

which means that the function w in terms of - 7 equals 9

the question is how much is the value of the function w (x) when x = - 7, that is, again:

w (-7) = 9

w (x) = y

so the value of y is 9