The equation "X = -2" indicates that the variable X is equal to the value of negative two. In mathematics, this means that whenever X is referenced, it represents the number -2. This is a simple linear equation, often used in algebra to solve for unknown values. In a number line, -2 is located two units to the left of zero. It is part of the set of negative integers, which includes numbers like -1, -2, -3, and so on. Understanding this concept is fundamental in various mathematical applications, including solving equations and graphing functions.