Pre-Algebra 4 - Whole Numbers, Integers, and the Number Line

Number systems evolved from the natural "counting" numbers, to whole numbers (with the addition of zero), to integers (with the addition of negative numbers), and beyond. These number systems are easily understood using the number line.

[-----abhi-----]

'A thing of beauty is a joy forever' - just like knowledge and these videos. Thank you creators for the effort you've put so that its easy for people like me to understand these concepts thoroughly.

[jakesarms]

The best pre algebra explanation I ever heard - can't wait to show my kids.

[JRskatr]

I also have explained it similar to your way, if you're adding a positive number on the number line you are going to the right, so adding a negative must mean you're going to the left. If when you add a positive number you go right, when you subtract a positive you must be going left. Thus, since the negative made you go in the opposite direction, when you subtract a negative number you are now going back to the right, which means the same as adding a positive number.

[JRskatr]

I also had some difficulty explaining the concept of subtracting a negative. It's easy to just remember when two minuses "touch" it turns to a positive (that's how I teach my algebra 1 students, it helps them a lot) but if one wants to know "why?" it gets a little tricky sometimes. If this happens I decided on explaining the negative sign as a sign for "opposite" and said if you're subtracting a negative, you're doing the "opposite" of the subtraction operation, which means you're now adding.

[JRskatr]

By the way, thank you SOOOO much for starting this series I stumbled upon it today when I typed in "history of math" in the search, because I wanted something to show my class since today was a review day for the midterm, and this was the first that popped up. It looked interesting so I clicked on the first video that showed up which was "The Dawn of Numbers" and my students were very intrigued by the video! They listened much better then when I speak! lol. Thanks again so much!!!

[najibqunoo]

6:40 another application of negative numbers is using cold temperatures of matters

[JuanHurtadorepre]

Great Job -MyWhyU-, Congrats from Medellín-Colombia.

[PatriciaMaeDanay]

Shesh, I shouldve discover this channel earlier!

[Subsandsoda]

subbed. Already knew most of the basic stuff, but it's brought entertainingly and very clear, hope you get a lot more subs, and make zortan's of video's ^^

[Rosecloudlyrics]

Wow, complicated words I understand like this is so awesome!

[gamergirl]

Your like the best teacher ever THX
U just got a subscriber 😀

[sereniarabbit]

i love the animatoin why dont my teacher just put this vid on shes mean! 

[siemmens]

wow exelent video. You got a new follower

[FreddieF]

And Natural numbers are closed under addition and multiplication, right?

[awneeshkrishna]

my whyU is amazing . thanks 4 your help :D

[your_self]

My brother does this to and he likes it.😀😀😀

[FreddieF]

Isn't 0 also the subtractive identity? And isn't 1 also the divisional identity?

[MatheusHenrique-ypxn]

2:30 But isn't distances just quantities of space?

[edug]

This made me think, okay a plane is 2D, but 1D is a point or a line of a plane?

[Jordloopin]

1-15 of the videos in this series is my homework :(