An algebraic constant is a symbol that represents an unchanging number or is simply a number in an algebra equation. The term “constant” is the opposite of “variable.” For example, consider the algebra equation: y = 2 + x. Here y and x are variables and 2 is a constant that is to be added to x when finding y. This equation could also be written y = a + x if we explained that in this equation, a always = 2.

Here a would represent any number that is unchanging, but only in the context of working this equation, not in the context of the entire physical universe (a physical constant or constant of nature). The constant a could be 2 or 5.37 or 824 or… any unchanging number. Let’s say that a = 2; that is, the constant in this equation is 2. Then, we could allow x to be any number, add 2 to it, and find the value of y. So, if at one time, x = 1, then add 2 to x and y = 3. If at another time, x = 4, then add 2 to x and y = 6. Here the term “constant” is used in contrast to a “variable.”