Explanation:
you might have made some mistakes in the description.
I see the following equation :
5×log5(9 - x) = 6
that means log to the base of 5.
log5(9 - x) = 6/5
and now we put everything up as power of 5 :
5^log5(9 - x) = 5^(6/5)
9 - x = 5^(6/5) = 6.898648307...
x = 9 - 6.898648307... = 2.101351693...
but has this anything to do with the responses you have listed ? no.
so, I think there is something missing or mistyped.