Lesson 4: Properties of Operations6.AT.7

I can…

I can use the commutative, associative, and identity properties to rewrite expressions.

Key words

• Commutative Property — You can change the order and get the same answer.
• Associative Property — You can change the grouping and get the same answer.
• Identity Property — Adding 0 or multiplying by 1 keeps the same value.
• Property — A rule that is always true in math.
• Distributive Property — Multiplying a number by everything inside the parentheses: a(b + c) = ab + ac.

Steps

1. I have 3 guitarists, 5 drummers, and 2 keyboard players.
2. I can add them as 3 + 5 + 2, which gives 10.
3. The Commutative Property says order does not matter: 5 + 3 + 2 also gives 10.
4. The Associative Property says grouping does not matter: (3 + 5) + 2 = 3 + (5 + 2), both equal 10.

Try it

Which property is shown? (8 + 5) + 2 = 8 + (5 + 2)

Check your answer

Associative Property

The grouping (parentheses) changed but the numbers stayed in the same order, so this is the Associative Property of Addition.

Sentence starter

I know ___ because ___.

Goal: I can explain my reasoning using the words commutative property, associative property, and identity property.