Key learning points

1. Bar models can be used to compare expressions.
2. If the expressions are equal the bars will be the same length.
3. Operations can be performed on the bars that maintain equality.
4. This can be extended to operations on statements expressed algebraically.

Common misconception

Keywords

• Equation - An equation is used to show two expressions that are equal to each other.

• Variable - A variable is a quantity that can take on a range of values, often denoted by a letter.

• Constant - A constant is a term that does not change; it contains no variables.

• Like terms - Like terms are terms that have the same set of variables and corresponding exponents.