**Find a least common denominator**

We add or subtract rational expressions with different denominators by first writing them with a common denominator, usually the least common denominator (LCD).

**Finding the Least Common Denominator**

** Step 1 **Factor each denominator.

* Step 2 *Find the least common denominator.

**The LCD is the product of all different factors from each denominator, with each factor raised to the**.

*greatest*power that occurs in any denominator