The equation "x = 7" indicates that the variable x is equal to the number 7. 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 a quantity in a problem. In this case, if you were to substitute x with 7 in any equation, the equation would hold true. For example, in the equation x + 3 = 10, replacing x with 7 gives 7 + 3 = 10, which is correct. This illustrates how variables can represent fixed values in mathematical expressions.