Answer
$x=10$
Work Step by Step
RECALL:
$\log_b{a}=y \longrightarrow b^y=a$
With $a=x-1$ and $b=3$, use the rule above to the given expression to obtain:
$3^2=x-1
\\3(3)=x-1
\\9=x-1$
Add $1$ on both sides of the equation to obtain:
$10 =x$