Two expressions are equivalent when they always give the same value. To test that, you substitute a number into each and check they match. So this lesson runs on plugging a number into a box and on knowing order doesn't change a sum or product. 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 a number in place of an empty box or shape.
Example: If ▢ = 2, then ▢ + 3 becomes 2 + 3.
Level 1 Having the same value as something else.
Example: 2 + 3 and 3 + 2 are equal because both make 5.
Level 1 To put numbers together to find how many in all.
Example: 4 + 2 = 6.
Level 1 You can add or multiply in any order and get the same total.
Example: 2 + 3 = 3 + 2 = 5.
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. If ▢ = 2, what is ▢ + 3?
2. If ▢ = 2, what is 3 + ▢?
3. Do 2 + 3 and 3 + 2 give the same value?
Vocabulary previewed and basics checked. Time to start the lesson.
Start Lesson 6-6 →