Combining rational expression with unlike denominators

The video tutorial explains how to work with rational expressions by first identifying the need for like denominators. It emphasizes simplifying expressions through factoring and rewriting equations. The process of finding the least common multiple (LCM) of denominators is detailed, followed by combining terms and solving for constraints. Finally, the tutorial identifies restrictions by determining values that make the denominator zero.

Explain the process of determining the constraint for the variable Y in the given expressions.

Why is it important to identify values that make the denominator equal to zero?