The equation "X = 57" indicates that the variable X is equal to the number 57. In mathematics, this is a simple expression that shows a relationship between a variable and a specific value. It can be used in various contexts, such as solving equations or representing quantities. In practical terms, if you encounter "X = 57" in a problem, it means that whenever you see X, you can replace it with 57. This concept is fundamental in algebra and helps in understanding how to manipulate and solve equations effectively.