Answer:
8
Step-by-step explanation:
The attached graph shows the inverse function (red) and the value of the inverse function for an input of -9.
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The inverse function tells you the input required for the given output from the function. So, you can look for an output of -9 on the graph of <em>f</em> and see what input gives that. You find ...
f(8) = -9
so ...
f⁻¹(-9) = 8