Use And Interpret Algebraic Notation

Understand the key idea

Algebra uses letters to represent numbers that may vary or are not yet known. A term can contain a number coefficient and a variable, an expression combines terms and operations, and an equation states that two expressions are equal.

Common mix-up

Writing 3x means three multiplied by x, not 3 plus x. An expression such as 3x + 2 has no equals sign, while an equation such as 3x + 2 = 14 can be solved.

Try this first

1. Identify each quantity and choose a clear variable for the unknown value.
2. Translate operation words such as total, difference, product and shared equally into symbols.
3. Read the algebraic expression back in words and check that it matches the original situation.

Ask: What does each variable and operation represent in the original problem?