Question 960976
{{{8^x=16^(-1)}}}


{{{(2^3)^x=(2^4)^(-1)}}}  -------this one and...


{{{2^(3x)=2^(-4)}}}----------this one,
seem to be the missing steps.


{{{3x=-4}}}


{{{x=-4/3}}}


You might be able to jump through steps in your head and not feel the need to write them, but other people cannot always see through what you skipped.