The properties of operations are patterns you already use — you can add or multiply in any order and get the same answer, and adding 0 or multiplying by 1 changes nothing. So this lesson runs on quick addition and multiplication facts. Warm those up first.
These are words you'll need to already know to follow this lesson — not the new words the lesson teaches. Review each one, its meaning, and the example so the new lesson makes sense from the start.
Level 1 To put numbers together to find how many in all.
Example: 3 + 5 = 8.
Level 1 To add the same number many times to find a total.
Example: 2 × 4 = 8.
Level 1 The number that means nothing. Adding 0 does not change a number.
Example: 7 + 0 = 7.
Level 1 The number 1. Multiplying by 1 does not change a number.
Example: 9 × 1 = 9.
These check the skills you'll need for this lesson — not the new lesson itself. Answer all 3, then press Show my path. No grade — it just suggests where to start.
1. Does 3 + 5 equal 5 + 3?
2. Does 2 × 4 equal 4 × 2?
3. What is 7 + 0?
Vocabulary previewed and basics checked. Time to start the lesson.
Start Lesson 6-4 →