Combining Like Terms: Grade 9 math

What this covers

Combining Like Terms is taught in Grade 9 (age 14 to 15) as a main teaching focus. It sits in the Algebra strand.

Worked example

Difficulty scale

The sheet generator offers five difficulty settings for this topic.

1. Single variable with positive coefficients, e.g. 3a + 5a
2. Two variables with positive coefficients, e.g. 3x + 4y + 2x
3. Two variables including negative coefficients, e.g. 5a - 2b - 7a + 4b
4. Expressions with powers, distinguishing between x and x^2 terms
5. Expressions involving multiple variables and powers, e.g. 3x^2y - xy + 2x^2y

Common mistakes

• Combining unlike terms, such as writing 3x + 2y as 5xy
• Failing to associate the preceding sign with the term that follows it

Curriculum links

Indicative matches to Common Core State Standards. Check wording and codes against the official document.

• Use the structure of an expression to identify ways to rewrite it, such as factoring quadratic and polynomial expressions.