What is the difference between an equation and an expression?

Solution:

An expression is a mathematical way of expressing a situation 

Examples: 2x + 5, 10a, 20, (a + b), etc

An equation is obtained when we connect two expressions by an equal sign.

Examples: 2x + 5 = 105, 10a = 20, 20 = a, (a + b) = 30, etc

So, an expression is a mathematical way of expressing a situation. It is just a number, or only a variable, or a combination of numbers, variables, and operation symbols. An equation is obtained when we connect two expressions by an equal sign.

What is the difference between an equation and an expression?

Summary:

An expression is a mathematical way of expressing a situation. An equation is obtained when we connect two expressions by an equal sign.