Given information: We are given that f−1(−25)=7, which means that when the inverse function of f is applied to −25, the result is 7. This implies that applying the function f to 7 should give us −25, because the function and its inverse undo each other.
Implication of given information: Since we know that applying f to 7 should give us the value that, when the inverse function is applied, gives us 7, we can conclude that f(7)=−25. This is by the definition of inverse functions: if f−1(x)=y, then f(y)=x.
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