When it is said that "Y is a function of X," it means that Y is dependent on X. In other words, the value of Y is determined by the value of X. In mathematical notation, we typically represent this relationship as Y = f(X), where f is the function that relates the two variables. For example, if we have the equation y = 2x + 3, we can say that Y (or y) is a function of X (or x), as the value of y is determined by the value of x. On the other hand, if we have an equation like x = 2y + 3, it represents X as a function of Y, meaning the value of x is determined by the value of y.
