Does an algebraic expression have a single value? Explain?

Step 1
Algebraic Expression
An algebraic expression is a mathematical statement consisting of operators like ${\displaystyle (+,-,÷,\times \dots ..)}$ and operands like variables, constants. Some examples of algebraic expression are ${\displaystyle 2x-5,y^2+4,3xy-9}$ ....etc.
Algebraic expressions are the building blocks for an algebraic equation. Multiple algebraic expressions when put either side of an = sign, form an algebraic equation.
These algebraic equations are used to determine the values of the unknown variables in the equation.
Some examples of the algebraic equations are ${\displaystyle 2x-5=11,y^2-4=y,a^2+b^2=25}$, ....etc.
It must be noted that, given an algebraic expression, the value of the expression at some particular values can be determined, or the terms in that expression can be manipulated from one form to another, using the basic principles of mathematical algebra.
Step 2
However, an algebraic expression can not be actually solved on its own. So one cannot talk about the value of the expression, unless and until the values of the unknown variables are specified.
What one can actually solve is the algebraic equation formed by the expressions. The number of solutions of an algebraic equations depend on the type of equation, which is being solved. A linear algebraic expression corresponds to a single valued solution, a quadratic algebraic expression corresponds to two solutions, a cubic algebraic expression corresponds to three solutions,....and so on.
Thus, it is concluded that an algebraic expression can possess a value, if all the variables in the expression are known, but still it is not necessary that the expression always yield only a single value.

Answer:
Constants are the terms in the algebraic expression that contain only numbers. That is, they're the terms without variables. We call them constants because their value never changes, since there are no variables in the term that can change its value.

Constants are the terms in the algebraic expression that contain only numbers. That is, they're the terms without variables. We call then constants because their value never changes, since there are no variables in the term that can change its value.