Difference Between Expression and Equation

Expression vs Equation

Expression and Equation are terms that are very often encountered in mathematics. However, if you were to ask the difference between an expression and an equation to even those who are students of Math, chances are you may not get a satisfactory answer. Both are however important in understanding different concepts in Mathematics. Both make use of numbers and variables, however, the difference lies in their arrangement. This article will highlight the differences between the expression and equation and make it easier for you to pick up an equation from an expression.

While an equation is a sentence, an expression is a phrase. For example, ‘Ten is five less than a number’ is an equation that can be represented by a formula.

10= x-5.

On the other hand, a number less than five is a phrase, and hence an expression.

If you are given an expression A+2A, you cannot make out anything unless you know the value of the variable A. So, while A+2A is just an expression, A+2A=3A becomes and equation.

An equation is a combination of two expressions usually separated by an equals sign, which means that both expressions must equal each other. For example x-4=5 means x can have only one value that is 9.

An expression can be evaluated, whereas an equation can be solved. An expression is basically an incomplete mathematical equation. It cannot have an answer or solution.

If we compare with English language, an equation is like a complete sentence, while an expression is just like a phrase. If you have any difficulty in identifying an equation or an expression, looking for the equality sign will remove all your doubts. Knowing that equations involve relationships, it is easy to identify a mathematical equation. Also, when you see an equation, you have to solve it to arrive at an answer, whereas you only evaluate an expression.


• Equations and expressions are often encountered when understanding mathematical concepts.

• If compared with language, expressions are like phrases while equations are complete sentences.

• Expressions have no relations whereas equations reveal relationships.

• You need to solve equations while expressions can only be evaluated.

• Equations have an equality sign while expressions do not have any equals sign.