Square roots and real numbers | Pre-Algebra | Khan Academy

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Pre-Algebra on Khan Academy: No way, this isn't your run of the mill arithmetic. This is Pre-algebra. You're about to play with the professionals. Think of pre-algebra as a runway. You're the airplane and algebra is your sunny vacation destination. Without the runway you're not going anywhere. Seriously, the foundation for all higher mathematics is laid with many of the concepts that we will introduce to you here: negative numbers, absolute value, factors, multiples, decimals, and fractions to name a few. So buckle up and move your seat into the upright position. We're about to take off!

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[TMichH]

I learned more in 10 minutes than I did in a week of class. Thanks!

[realkabecio]

Sal Khan makes learning math so easy!! He also sounds happy when hes doing it and that crosses over to the learner. His teaching has helped me get over my dread of math and stopped my being bored by math explanations.

[cemorellilover]

thank you so much your videos are so helpful, i used to think math is hard but now i love math! thanks again.

[zachmorgan]

If you don't get it you're not alone! The best way for me is to do it for 30 minutes stop and come back to it and if I don't get it the first time I will the second or third.

[noushka]

wow awesome!! helped me understand it better!

[kaitlincassell]

Thanks Khan Academy. I am an alp in class and we are learning about square roots in the homework.

[pharks]

Literraly learning this in grade 8 and it is HARD af for me XD

[meghjibhaimaheshwari]

Found it helpful and fascinating. Keep up the good work 👍🏻👍🏻

[adityac]

Sal,
you're the best teacher ever

[mujmirza]

Thank you sal you help everyone out so much :D

[gotlovemycomment]

this is a REALLY useful vid, thank you so much!

[hoodedmantis]

thanx you helped me with my homework :)

[fatimadepoet]

Thank you for the examples there were very beneficial! :)

[christinamakeup]

I just Khan thank you thank you thank you

[orecreeper]

I'm glad no one says "why u no take beacon from well" here, it's driving me nuts!

[brandonmurphy]

THANK YOU SOOOO MUCH. This helped me so much with algebra 1

[Kenneth-mjhk]

Thank you so much! It really helped me understand

[isaacnydegger]

This helped me so much! Just subscribed!

[ruthsalgado]

Thank so much Mr. Sal! This is very helpful to me :))

[amirajcmusic]

Great video! Thanks for clearing things up!