Question

I need some help with a word problem, I just need someone to check my answer for me, so if anyone is up to it, please and thank you! :)

I will post the question and my answer below...

Answer 1

The Question:

Nakim simplified 3√2x+x√8x-5√18x got -10x√2x for an answer.

Part 1: Using complete sentences, explain what Nakim did wrong.

Part 2: Show all your work to simplify the expression.

Answer 2

My Answer:

Part 1:
Nakim would have missed the x in the middle term, and had combined all to get -10 sqrt(2x)

but the solution actually is
2 (sqrt(2x))(x-6)


Part 2:
First, you have to simplify the expression

3sqrt(2x)+ xsqrt(8x) - 5sqrt(18x)

8=2^2*2
18=3^2*2
so , the expression is now:

3sqrt(2x) + xsqrt(4*2x) - 5sqrt(9*2x)
= sqrt(2x) + 2xsqrt(2x) - 15sqrt(2x)


Is this right?

Answer 3

With the solution being: 2 (sqrt(2x))(x-6)

Answer 4

xsqrt8x =2xsqrt2x
5sqrt18x =15sqrt2x

3sqrt2x +2xsqrt2x -15sqrt2x =2xsqrt2x -12sqrt2x =(x-6)2sqrt2x

Answer 5

ohh, so...
3*sqrt(2x) + x*sqrt(8x) - 5*sqrt(18x becomes:
3*sqrt(2x) + 2x*sqrt(2x) - 15*sqrt(2x).
then you can factor out the sqrt(2x) to get:
sqrt(2x) * (3 + 2x - 15) which results in:

sqrt(2x) * (-12 + 2x)?

thats another way I got it, would this be the way to write it?

Answer 6

so 3sqrt2x and -15sqrt2x because are the same terms you can assum these

Answer 7

this is weird, I just went onto my Algebra solving program (it just gives you the answer without explaining) and it said that the answer is actually this:
-12sqrt2x + 2xsqrt2x?

Answer 8

and after make the GCF - great common factor - what will be

Answer 9

yes is right but from this you can subtracting again the GCF what will be 2sqrt2x

Answer 10

but how did it get that answer? neither of our solutions equaled -12sqrt2x + 2xsqrt2x?

Answer 11

check my calcules

Answer 12

ohhh I see it now, sorry I missed that

Answer 13

So this would be the whole answer:

3sqrt(2x)+ xsqrt(8x) - 5sqrt(18x)

xsqrt8x =2xsqrt2x
5sqrt18x =15sqrt2x

3sqrt2x +2xsqrt2x -15sqrt2x =2xsqrt2x -12sqrt2x =(x-6)2sqrt2x

Answer 14

yes exactly

Answer 15

But I had to break it up like this...

3sqrt(2x)+ xsqrt(8x) - 5sqrt(18x)

xsqrt(8x) = 2xsqrt(2x)
5sqrt(18x) = 15sqrt(2x)

3sqrt(2x) + 2xsqrt(2x) -15sqrt(2x)
= 2xsqrt(2x) -12sqrt(2x)
=(x-6)2sqrt(2x)

Answer 16

Okay cool, but what about the 1st part of the question, the one asking what Nakim missed... Does what I put sound good?

Answer 17

I mean it could be this to:

the answer given was sqrt(2x) * (-10x)
looks like nakim combined 3 + 2x - 15 to get -10x.
the 3 and the -15 could be combined because they're like terms.
however, the 2x could not be combined because it was different from them. it included an x in the term which the others did not have. Therefore, since they are not like terms, the answer couldn't possibly be (2x)*(-10)??

would that be right?

Answer 18

so if you will check it there 3sqrt2x +2xsqrt2x not is equal 5xsqrt2x but Nakim have considered hence and Nakim have subtracted this 5xsqrt2x from 15sqrt2x and hence have got this result of -10xsqrt2x

Answer 19

ahhh, thank you so much!! :)

Answer 20

yw
was my pleasure
good luck

bye

Answer 21

you really are a big help!

Answer 22

bye