#### Answer

The domain is $\left\{t| t\ne -2\right\}$.

#### Work Step by Step

The denominator of an expression is not allowed to be equal to zero.
To find the value of $t$ that will make the denominator zero, solve the equation:
$3t+6=0
\\3t=-6
\\\frac{3t}{3}=\frac{-6}{3}
\\t=-2$
The given expression's denominator will be equal to zero when $t=-2$.
Thus, the value of $t$ cannot be $-2$.
Therefore, the domain of the given expression is the set of all real numbers except $-2$.