Answer
$x=\frac{-1}{5}$
Work Step by Step
RECALL:
$\log_a{x}=y \longrightarrow a^y = x$
Use the rule above to obtain:
$\log_6{36}=5x +3
\\\longrightarrow 6^{5x+3}=36$
Note that $36=6^2$. Thus, the expression above is equivalent to:
$6^{5x+3}=6^2$
Use the rule $a^m=a^n \longrightarrow m=n$ to obtain:
$5x+3=2$
Subtract by 3 on both sides of the equation to obtain:
$5x=2-3
\\5x=-1$
Divide by 5 on both sides of the equation to obtain:
$x=\frac{-1}{5}$