What is the difference between an equation and an expression?

An expression is a combination of numbers, variables, and operations, but it does not have an equal sign. For example, "x + 3" is an expression. An equation, on the other hand, shows that two expressions are equal and includes an equal sign, like "x + 3 = 7". Equations can be solved to find the value of the variable, while expressions can only be simplified or evaluated. Recognizing this difference is important because solving equations involves finding unknown values, while expressions are used to describe relationships or compute values.