Answer
$x = 0$
Work Step by Step
The least common denominator, or LCD, is $x + 1$.
Multiply each side of the equation by $x + 1$ to eliminate the fractions:
$$\begin{align*}
(x+1)\cdot \frac{3x}{x+1}&=0 \cdot (x+1)\\
\\3x &= 0
\end{align*}$$
Divide each side of the equation by $3$:
$$\begin{align*}
\frac{3x}{3}&=\frac{0}{3}\\
x &= 0
\end{align*}$$
To check the solution, plug in $0$ for $x$ into the original equation:
$$\begin{align*}
\frac{3(0)}{0 + 1} &\stackrel{?}{=} 0\\
0&\stackrel{\checkmark}{=}0
\end{align*}$$
