Question 20724
i think you mean logs to base 8 ...assuming that and using the formula 
log x to base y = log x /log y...where all logs are taken to any common base.
so we have
log(n-3)/log 8 + log(n+4)/log 8 =1....multipling through out with log 8,we get
log (n-3)+log (n+4)=log 8
log(n-3)(n+4)=log 8
hence (n-3)(n+4)=8
n^2-3n+4n-12-8=0
n^2+n-20=0
n^2+5n-4n-20=0
n(n+5)-4(n+5)=0
(n+5)(n-4)=0
hence n=-5 or n=4