#### Answer

$x(x+3)$

#### Work Step by Step

We are given the denominators $x+3$ and $x$.
In order to find the least common denominator, we must factor each denominator.
$x+3$ cannot be simplified further
$x$ cannot be simplified further
Next, we multiply together all distinct factors from each denominator, with each factor raised to the greatest power that occurs in any denominator.
$LCD=x\times(x+3)=x(x+3)$