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## Class 8 (Foundation)

### Course: Class 8 (Foundation)>Unit 4

Lesson 3: Additive and multiplicative inverse

# Inverse property of addition

The simple idea that a number plus its negative is 0. Created by Sal Khan.

## Want to join the conversation?

• what does property mean in math?
• Commutative Property. The word "commutative" comes from "commute" or "move around", so the Commutative Property is the one that refers to moving stuff around. For addition, the rule is "a + b = b + a"; in numbers, this means 2 + 3 = 3 + 2. For multiplication, the rule is "ab = ba"; in numbers, this means 2×3 = 3×2.
• If you did this problem (-6) + 5 = -1 would it be inverse property of addition?
• -6 + 5 = -1
So you cant do anything cause you have all three numbers
• how do i do Inverse property of addition?
• All you have to do is add the inverse number to the original number. Like 1/2 + (-)1/2 = 0.
• ok I get this but I want to work someone else's brain. How do you get to zero from the answer of 5/2 * 42,000 squared? =) I can't write exponents on the computer easily. :) ;) :)
• You get the answer to that and then add it's additive inverse to it
• Omg, Thanks Im so confuzzled! I didn't get it intill you, Sal!
• Why does algebra have letters for numbers in equations?
• The variable or as I like to call it: x, is used to define a number whose value is unknown. Usually, using the clues around the variable, you have to find out what the value of x could be.
(1 vote)
• how can we do this with additive inverse (-46)+(-72)=?
(1 vote)
• The additive inverse property does not apply to your problem. The additive inverse property says: a number + it's opposite = 0. Example of the additive inverse property are: 3 + (-3) = 0; or -5 + 5 =0.