hmm
remember
[tex]a^c=b[/tex] can translate to [tex]log_a(b)=c[/tex]
so
[tex]5^{3x}=15[/tex] can translate to [tex]log_5(15)=3x[/tex]
divide both sides by 3
[tex](1/3)log_5(15)=x[/tex]
[tex]log_5(15^{1/3})=x[/tex]
use calculator, if you can't use change of base formula to do it
[tex]log_a(b)= \frac{log_c(b)}{log_c(a)} [/tex] so
[tex]log_5(10^{1/3})= \frac{log_{10}(15^{1/3})}{log_{10}(5)}=x [/tex]
evaluate using base 10 on your calculator
0.560869=x
