The equation "X = 55.5" indicates that the variable X is equal to the numerical value 55.5. This means that whenever X is referenced in a mathematical context, it represents the specific quantity of 55.5. This type of equation is commonly used in algebra to define relationships between variables. In practical applications, the value 55.5 could represent various things, such as a measurement in temperature, weight, or score. Understanding that X equals 55.5 allows for further calculations or comparisons to be made based on this established value.