The equation "X = 45" indicates that the variable X is equal to the number 45. In mathematics, this is a simple expression that shows a specific value assigned to a variable. It can be used in various contexts, such as solving equations or representing quantities in a problem. In practical terms, if you encounter "X = 45" in a scenario, it means that whatever X represents has a fixed value of 45. This could apply to measurements, scores, or any other numerical data where X is defined. Understanding this concept is fundamental in algebra and other areas of mathematics.