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## Arithmetic

### Course: Arithmetic>Unit 18

Lesson 7: Adding & subtracting integers

# Addition & subtraction: find the missing value (part 1 of 2)

Sal solves some missing value problems: -1 = 7 - __ and -10 + __ = -5 and 4 = -2 + __ and 6 + __ = -8.

## Want to join the conversation?

• I get very confused when you use number lines because then I do not know how to do it the non-visual way. Do you think you could maybe still do number lines, but also do it without the number lines? I think it would help me and other people who don't really do visuals. And other people who like number lines can still understand. Thank you so much for considering this and making these videos!
• Using a mental number line is not something everyone can do right away it takes time, some people think more visually, and some people don't. But there's nothing wrong with that, so when doing a problem have a piece of paper with a n line and eventually you'll get where you don't need it.
I hope this helps! :)
• In which sitution would I need this
• Teachers prepare us for whatever we do as an occupation in our lives. So there wouldn't be many times you would use this in everyday life but I bet there is some job where you could use this. (And it's just good knowledge.)
• pls vote so i can get the badge
• I know some ppl don't understand what you're talking about but they just have to practice and listen so in the future they will need this and some of them won't have any idea but I appreciate you and your friends time making these videos online so we can all learn I really appreciate it for you taking your time of day just to help others be educated and learn new things everyday that's really sweet of you and your teammates and I thank you for at least giving they a little laugh here and there in videos you are a really nice guy... thank you and your community so much for taking the time of your day, night or evening to help others gain knowledge that's very helpful and kind of you... thank you again just keep practicing guys you will be so good in no time!
:)
• That is one of the longest explaining thingy things I've ever seen🤣
• pls vote so i can get the badge
• All lot of confusion!

Basically, in the problem -1 = 7 - _, you'll just need to add 7 + I-1I and fill in _ with the result. The absolute on -1 is 1, so 7+1 = 8.

Now, let's complete the equation : -1 = 7 - 8

You may ask: How is this true? Well the explanation:

1. Breakdown 8 into two parts - 7 and 1
2. Subtract the bigger number (7) from the whole to get 0
3. Subtract the remaining of 8 from 0
4. 0 - 1 = -1

*That's it! You solved it!*
• *or you just put 8 there cuz 1 less than -7 is -8