How to approximate square roots | Numbers and operations | 8th grade | Khan Academy

Learn how to find the approximate values of square roots. The examples used in this video are √32, √55, and √123. The technique used is to compare the squares of whole numbers to the number we're taking the square root of.

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8th grade on Khan Academy: 8th grade is all about tackling the meat of algebra and getting exposure to some of the foundational concepts in geometry. If you get this stuff (and you should because you're incredibly persistent), the rest of your life will be easy. Okay, maybe not your whole life, but at least your mathematical life. Seriously, if you really get the equations and functions stuff we cover here, most of high school will feel intuitive, even relaxing. (Content was selected for this grade level based on a typical curriculum in the United States.)

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[MsGreenmachine]

He said at 4:32, he'd have to check that on the calculator but I want to know how I can solve without a calculator.

[jaz]

i freaking hate math omg its so fustrating

[cyanwise]

8th grade? Man I'm learning this in grade 7 😬

[lemon-socks]

I’m quarantined right now and this helped me so much

[jacobroden]

When he started the video I decided to solve for √123 (With Calculus). I had no idea he'd showcase that EXACT square root in this video. Crazy

[Asad-xuxm]

THANKS TO YOU I GOT AN 80 ON MY PREVIOUS MATH TEST AND THE CONCEPT WAS SO HARD AND YOU ALSO HELPED ME WITH THIS! THANK YOU SO MUCH! YOU DESERVE MORE THAN 4.3 MILLION SUBSCRIBERS! :D

[eaglead]

the different colors def help keep me focused

[mariah]

Thank you! This helped me understand my lesson better. =)

[rujandoru]

Is there a version thats not in decimals, PLEASE?

[alwaleedalabri]

My teacher uses this way and I can't understand anything

[fl]

how exactly do you find the decimal though

[KaraTalks-ndec]

Tysm! I hope I will make a decent grade on my test!

[militantpacifist]

I always thought that I had to divide by the closest square root, like 32/6.

[Itisheylel]

Thank you so much! Have a nice day everyone =D

[rouahejazi]

Imagine having math everyday with a man that's voice like that 😏.


No, but on a serious note it would be so fun and Alot easier to learn. Great explanation

[krishavatar]

I’m a 5th grader tryna learn this and it’s really easy

[TITZ]

dude you're better than my teacher i couldn't understand ANYTHING today and i couldn't ask a question bc i couldn't pinpoint what i didn't understand

[isabellark]

Omg thank you. I get it much better now!😄😄😄

[ryantilman]

Thank you so much this helped me so much!!

[Archived]

The only thing i got surprised by this is how he perfectly manage to draw a brace with no hesitation