## Precalculus: Concepts Through Functions, A Unit Circle Approach to Trigonometry (3rd Edition)

$4$
The domain of the variable requires that $x+6>0$, which means that $x>-6$. Recall: $y=\log_a{x} \implies a^y=x$ Thus, $\log(x+6)= 1 \\ \implies 10^1=x+6\\ \implies 10=x+6$ Solve the equation to obtain: \begin{align*} 10-6&=x\\ 4&=x \end{align*}