Answer:
whatever you define it to mean
Explanation:
In 2nd grade, you might see an addition facts problem that looks like ...
2 + ___ = 5
In Algebra, we might write the same problem as ...
2 + x = 5
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"x" is the name often given to an unknown quantity, or a quantity that may not have a specific known value at the time the expression or equation is written. It is one of several letters near the end of the English alphabet that may be used in this way.
By convention, "x" is the "generic" independent variable. The corresponding dependent variable is conventionally represented by "y". In this use, "x" shows up as the name of the horizontal axis on a Cartesian grid. Likewise, "y" is the name conventionally assigned to the vertical axis.
Coordinates on such a grid are represented as ordered pairs, with the horizontal coordinate listed first. That is "x" conventionally refers to the first element of an (x, y) ordered pair.
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In its role as an unknown quantity in an Algebra problem, "x" may stand for anything you like. It may represent the value the problem is asking you to find, or it may represent an intermediate result on the way to finding that value. That is, its role in any given problem must be defined. Often, but not always, this can be accomplished by the context in which it is found or used.
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In the above discussion, we have pretty much assumed that x is a one-dimensional variable, that may or may not have associated units. In some problems, x may represent something (or some collection of somethings) with multiple dimensions, the exact number of which may not be known. It may represent one or more data structures on any defined or undefined size or shape. The fundamental idea is that "x" can represent whatever you want it to represent.