Learn how to rewrite square roots (and expressions containing them) so there's no perfect square within the square root. For example, rewrite√75 as 5⋅√3.

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skilavera1

5 years agoPosted 5 years ago. Direct link to skilavera1's post “what grade maths would th...”

what grade maths would this be?

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(18 votes)

Beaniebopbunyip

5 years agoPosted 5 years ago. Direct link to Beaniebopbunyip's post “I think it’s about eighth...”

I think it’s about eighth or ninth grade. But people take math at different times. I’ve known fith graders who have taken algebra and geometry in the same year, and I’ve known ninth graders who have taken algebra. Even if you’re taking algebra in ninth grade, that’s okay. What really matters is that you understand the content when you learn it.

(71 votes)

Jaidyn McPherson

6 years agoPosted 6 years ago. Direct link to Jaidyn McPherson's post “when will we ever use thi...”

when will we ever use this in everyday life? whats the point of even learning this?

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(15 votes)

AD Baker

5 years agoPosted 5 years ago. Direct link to AD Baker's post “Jaidyn, After learning ...”

Jaidyn,

After learning this helps you pass your Math class and graduate high school, there are many careers where this is used. Most obviously, it's used in engineering and computer science. However, when I worked in construction, I used to use square roots regularly to determine whether items would fit through a doorway on a diagonal. (Note: this also involves trigonometry.)

(55 votes)

dylan.forr99

a year agoPosted a year ago. Direct link to dylan.forr99's post “Anyone else need to take ...”

Anyone else need to take like 4 or 5 hours to really get a firm understanding of this lesson? or am I just dumb?

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(17 votes)

Gina

a year agoPosted a year ago. Direct link to Gina's post “Sometimes things snap rig...”

Sometimes things snap right into place and the light goes on right away, and other times we need review and practice. If you got this far, you already have all the pieces you need to work with radicals. It's a matter of seeing how they go together.

(9 votes)

bjacobsen4427

a year agoPosted a year ago. Direct link to bjacobsen4427's post “golly gracious i think iv...”

golly gracious i think ive passed out 15 times trying to these

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(21 votes)

Ha

6 years agoPosted 6 years ago. Direct link to Ha's post “can a fraction be an expo...”

can a fraction be an exponent?

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(10 votes)

Redapple8787

6 years agoPosted 6 years ago. Direct link to Redapple8787's post “A fraction can be an expo...”

A fraction can be an exponent. When a fraction is an exponent, you can change it so that a there is a first, second, third, etc. root of something.

For example,

1^1/2 = square root of 1

1^1/3 = third root of 1

1^1/4 = fourth root of 1

And so on and so forth. This was covered in a series of videos in the topic Rational Exponents and Radicals.

https://www.khanacademy.org/math/algebra/rational-exponents-and-radicals/alg1-rational-exp-eval/v/fractional-exponents-with-numerators-other-than-1(15 votes)

Lateo

8 years agoPosted 8 years ago. Direct link to Lateo's post “In the video "Simplifying...”

In the video "Simplifying square roots (variables)" @

1:40

Sal explains "as I said in the last video, the principal root of X squared is going to be the absolute value of X, just in case X is a negative number". I have two questions:

(1) Can anybody please point me to that video? I can't find it.

(2) I don't understand the need for an absolute value. If we state, before beginning to solve the problem, that the domain of the X variable is the Positive Real Numbers (or X greater than or equal to zero), aren't we already cancelling out the possibility that the X variable assumes a negative value by restricting the domain, thus rendering the use of the absolute value unnecessary?•

(11 votes)

Nathan Adams

7 months agoPosted 7 months ago. Direct link to Nathan Adams's post “No question..just a thank...”

No question..just a thanks for helping me remind myself of all that I've forgotten. I have an Associate in Civil Engineering degree from 47 years ago! I am now 84 years old and spent 26 years doing land and construction surveying. I love COGO and can run circles around Coordinates, etc. But, my love of math has never ended, and to be honest, doing Simplifying Square-Root Expressions, has thrown me into a tither! Can't believe I flunked twice! Very, very frustrating at times. Oh, what stirred my extreme interest into Math was my high school Trig teacher! He, Mr. George Aherns showed how to measure the distance across a river

without crossing the river and how does a tunnel go inside one side of a mountain and come out exactly on the other side without climbing the mountain. Think about that, all you anti-Algebra terrorists!!•

(11 votes)

will.lindner.student

6 years agoPosted 6 years ago. Direct link to will.lindner.student's post “what about problems with ...”

what about problems with a number already multiplying the square root. Do you multiply or add the numbers together?

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(5 votes)

David Lee

6 years agoPosted 6 years ago. Direct link to David Lee's post “It's easier to understand...”

It's easier to understand if there is an example. Let's say you have √98. 98 is 49*2 which is 7^2*2, it would be 7√2. If you have 2√98. √98 is 7√2, 2√98 would be 14√2.

Hope this helps! If you have any questions or need help, please ask! :)

(9 votes)

Misheel

3 years agoPosted 3 years ago. Direct link to Misheel's post “Can i also simplify √72 ...”

Can i also simplify √72 in this way: √72 = √9*8 = √9*√8 = 3√8

instead of: √72 = √2*36 = √36*√2 = 6√2

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(3 votes)

Kim Seidel

3 years agoPosted 3 years ago. Direct link to Kim Seidel's post “Yes, you can take that ap...”

Yes, you can take that approach. But, your work is incomplete. When you simplify a square root, you need to ensure you have removed all perfect squares. With 3√8, you still have a perfect square inside the radical.

3√8 = 3√(4*2) = 3√4 * √2 = 3*2√2 = 6√2

Hope this helps.(12 votes)

Phil

5 months agoPosted 5 months ago. Direct link to Phil's post “What's the most efficient...”

What's the most efficient way to finding all perfect squares?

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(4 votes)

Menschinator

5 months agoPosted 5 months ago. Direct link to Menschinator's post “``` _edit_x x...”

*edit*

x x^2 x^3 x^4.......

1 1 1 1

2 4 8 16

3 9 27 81

4 16 64 256

5 25 125 625

6 36 216 1296

7 49 343 2401

8 64 512 4096

9 81 729 6561

10 100 1000 10000

11 121 1331 14641

12 144 1728 20736

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I would advise keeping a little chart like this nearby in the beginning to get used to perfect squares....

after time things will start standing out if they seem like they are perfect squares....(10 votes)