Question

How are the graphs of inverse functions symmetric?

Answer 1

plot the graphs then pot y = x

and see what happens

Answer 2

if the graph of \(f\) contains the point \((a,b)\) then the graph of \(f^{-1}\)contains the point \((b,a)\) i.e. it switches the \(x\) and \(y\)
as @campbell_st wrote, graph \(y=x\) and you will see the symmetry