#### Answer

Fill the blank with
... $(b, a)$ ...

#### Work Step by Step

Graphing the inverse of a function can be done by reflecting the graph over the line $y=x$.
Points (x,y) and (y,x) are symmetric relative to the line $y=x,$
so, as stated in "Important Facts about Inverses" on p.414,
3. If the point $(a, b)$ lies on the graph of $f$, then $(b, a)$ lies on the graph of $f^{-1}$.