Question

Meh. I don't understand square roots. xD Help, please? I'll type up the problem in the comments.

Answer 1

Nakim simplified \[3\sqrt{2} + x \sqrt{8x} - 5\sqrt{18x}\] and got \[-10x \sqrt{2x}\] for an answer.

Explain what Nakim did wrong, and then simply the expression correctly.

Answer 2

sqrts are just like factors; you can treat them as an extra variable if need be

Answer 3

notice that the first one aint got no x in it, so it aint like the others.

Answer 4

I'm confused. :/

Answer 5

im sure you are, but i cant read minds so youll have to be more specific in your condition.

Answer 6

How would I simplify the expressions so I can solve it?

Answer 7

take out the perfect squares that are inside of them

Answer 8

can you list the first few perfect squares? up to 5^2 should suffice for this

Answer 9

Wait, what? D:

Answer 10

what does "wait what" mean???

Answer 11

I don't understand what you're asking me to do. :/

Answer 12

take the first few numbers; 1 - 5 and square them

Answer 13

whgwertgwhrteg;rgje what first few numbers? x.x

Answer 14

I seriously don't understand anything you're asking me to do. :/ I don't understand square roots at all.

Answer 15

apparently you dont understand; first few numbers 1-5 either, or what it means to square them ....

Answer 16

Apparently not. ._.

Answer 17

then your not understanding more than just square roots

Answer 18

Can't you just show me how to simplify one of them and I can use it to help me figure out the other ones? :/

Answer 19

im trying, but you dont understand

Answer 20

a square root undoes a square

Answer 21

what is 3^2 ?

Answer 22

9?

Answer 23

yes, and what is 2^2 ?

Answer 24

4?

Answer 25

good, these will be all we need for this problem;

4 and 9 are called perfect squares since they can be undone by a square root

sqrt(4) = 2

sqrt(9) = 3

does this make sense?

Answer 26

does 8x have any perfect square factors?

Answer 27

2 and 4? o.o

Answer 28

yes :)

sqrt(8x) = sqrt(4*2x) = sqrt(4) * sqrt(2x) = 2 sqrt(2x)

that is the simplified version of sqrt(8x)

Answer 29

does 18x have any perfect square factors?

Answer 30

Oh. The first one is supposed to be 3 sqrt (2x), not 2

Answer 31

we should keep that in mind after we simplify the others then :)

Answer 32

and... 18 has 9 and 2. right?

Answer 33

9 and 2 are correct

sqrt(18x) = sqrt(9*2x) = 3sqrt(2x)

notice how we can undo a perfect square factor and pull it out

Answer 34

this leaves us with:
\[3\sqrt{2x}-x*2\sqrt{2x}-5*3\sqrt{2x}\]

Answer 35

So it would be.. 3 sqrt (2x) + 2 sqrt(2x) - 5 * 3sqrt(2x)

Answer 36

yeah.

Answer 37

yes, but dont forget the "x" term in the middle

Answer 38

oops. o.o

Answer 39

3sqrt(2x) + 2x sqrt(2x) -15sqrt(2x)

and the rest is history

Answer 40

So that means my final answer is.. 2x - 12sqrt(2x)?

Answer 41

if yo udo it that way, try using this for the notation

(2x - 12) sqrt(2x)

Answer 42

That was my answer before, and my teacher said to "review my final answer." which makes me think that's wrong. :/

Answer 43

its not wrong; but your teacher might want a different format

Answer 44

2x sqrt(2x) - 12 sqrt(2x) is another way to write it

Answer 45

What Nakim did wrong, is he ignored that the second term had a factor of x, and added all the terms together.
The real answer would be:
2x - 12sqrt(2x)

Response Feedback:
Please review your final answer.


^^ that's the response she gave me.

Answer 46

your notation is bad ...

put paranthesis around 2x - 12 to keep it as a single value

Answer 47

okay.

Answer 48

thanks. n.n

Answer 49

spose you had:

3n + 2xn -15n

2x -12n is not a proper simplification

Answer 50

True. I think I see what I did wrong. Thanks for the help. :

Answer 51

youre welcome