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## Kindergarten

### Course: Kindergarten>Unit 2

Lesson 4: Put together, take apart

# Addition and subtraction within 10

Sal solves addition and subtraction problems with number 10 or less.

## Want to join the conversation?

• So 1 + 4 is equal to 4 + 1 in . Is this the commutative law?
• Yes, very good observation. It is also called the Commutative Property of Addition.
• Commutative law, Commutative Property of Addition... there is a certain thrill in learning proper names for common operations through comments in early math!
• so 1+4=5 and 4+1=5 3+2=5 2+3=5
• Correct. There are infinite ways to make five though, so I wouldn't attempt to try all of them. :P
• why does it make me watch them 2 times
(1 vote)
• So you can make sure you understand everything.
• why doesn't this make sense
• when your doing this you can have it in different numbers and it can equal the same amount
• Yes! you can use different answers and get the sam amount.
• Is it related addition and subtraction
• Addition and subtraction are related with the fact that adding and then subtracting the same number will give you 0. Basically one undos the other.
(1 vote)
• why cant subtraction be backwards?
• you can subtract a negative number too , it same thing plu the absolute value of that negative number , you will learn that in grade 5 .