How to Simplify Expressions

Algebraic expressions are made up of letters and numbers. We call the letter the unknown. When a letter and number are together, such as 2b, we call this a term. When we simplify algebraic expressions we collect the like terms together. When term are alike they can be grouped together. This is known as simplifying the expression. An expression does not contain an equals sign. Simplifying refers to reducing the expression making it as small as possible. The example below shows groups of expressions. a, 7a and -4a are all the same term, a. -9b, b and 100b are all the same term b.

Simplifying Expressions - Harder Examples

Check out the example below. Some terms contain more than one variable. The term “2a” is different to the term “2ab” for example. If a = 3, let’s say, when you substitute it into 2a the answer is 6. If we substitute a = 3 into 2ab, the result is 6b. b is unknown. When we add 5xy with 2xy the answer is 7xy. However if the expression is 5xy + 2x we leave the simplification as it is. We do not combine 5xy with 2x because they are different variables. We can combine 5xy with 2xy since they belong to the same group "xy". The answer is 7xy.

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