Square Root Of Decimal (example) | Numbers And Operations | 8th Grade | Khan Academy

Learn how to find the square root of a decimal number. The problem solved in this video is p^2 = 0.81.

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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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16 thoughts

1. Marc Xu says:

I know u already did some gradient/slope videis but can u go into bisectors, gradient intercept formulae amd in general form (really in depth please) and also how to to convert from one to another.
If youbcould do this it would be much appreciated
Thanks

2. Lejla Rezania says:

Isn’t it 0.09 x 0.09 = 81 ? Or am I just confused with you telling us that 0.9 x 0.9 is 0.81?

3. Jamel Hudson says:

@Lejla 0.09×0.09 is 0.0081, the same way 0.5×0.5 is 0.25.

4. Raquel Cowan says:

Can you b my tutor I have a life changing exam coming up and I can use your help

5. T N says:

Wow, I never had to do that yet.

6. Ayush Jain says:

@Lejla Rezania : Sometimes when I get confused with this, I do the following:
0.9*0.9 = (9/10) * (9/10) = 81/100 = 0.81
This might help. CHEERS!

7. maxpolaris99 says:

not  very general

8. butthole_ says:

9. satish raj says:

what the square root of 0.4

10. krookyj says:

don’t mean to be mean, Mr. Khan, but shouldn’t .9 time .9 equal 8.1 instead of .81?

(*Edit:* wait, I was wrong. 8.1 is .9 times 9.)

11. slightly amused by ur trash content says:

link below to this post was written by a group of the most popular and its a good

12. sai pranay says:

13. Krabz says:

what would the square root of 5.76c^6?

14. Dhruv Pamnani says:

what is sqare root of 0.44

15. Dhruv Pamnani says:

what is sqare root of 0.44

16. The Playa says:

What is the square root of 6.1