Find the LCD for the following pairs of rational expressions.

numerator 8 divided by denominator x negative 13 and numerator 7 divided by denominator x plus 15

To find the least common denominator (LCD) for the given pairs of rational expressions, we first need to factor the denominators and identify the common factors.

Let's start by factoring the denominators:
Denominator 1: x(-13)
Denominator 2: x(+15)

Now, let's identify the common factors. Notice that both denominators have a common factor of "x". So, we can say that the common factors are "x".

To find the LCD, we need to take the product of all the factors with the highest power. In this case, we only have one factor "x", so the LCD for the given pairs of rational expressions is simply "x".

Therefore, the LCD is "x".