a QR problem...

[busdent]

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What is the value of x if (2(5/x+3))^1/2 = 10 ?

a. 3/7
b. 47/5
c. 5/97
d. 2/5
e. 5/47

Kaplan shows E as the answer and I keep on getting -29/10.

 

[Euphoria36]

the way you are doing it is (5/(x+3)) - doing it this way you get -29/10

the way kaplan is doing it is ((5/x) +3) and then you get 5/47 as the answer

from the way you set up the problem it's not clear on what the original problem states- so i did it both ways 🙂

 

[busdent]

What is the value of x if (2(5/(x+3)))^1/2 = 10 ?

a. 3/7
b. 47/5
c. 5/97
d. 2/5
e. 5/47

Kaplan shows E as the answer and I keep on getting -29/10.

I edited the problem. They show it as 2 times 5 over (x+3) and square root of the whole thing = 10

 

[caminito]

okay, if the problem is like this (your original post)

What is the value of x if (2(5/x+3))^1/2 = 10 ?

a. 3/7
b. 47/5
c. 5/97
d. 2/5
e. 5/47

then (e) is the answer, not -29/10. thus, kaplan was correct.

(2(5/x+3))= (10/x) + 6, so then

(((10/x)+6) ^(1/2))^2 = 10^2

(10/x) + 6=100
10/x= 100-6
10/x=94
10=94x
10/94= x
5/47 = x answer

10/2= 5
94/2=47

hope this helps. your edit problem is different from the first problem. but your answer was correct for the new problem.
your new problem is this after multiplication
(10/(x+3))^(1/2) = 10

which is not the same as

((10/x) + 6)^(1/2) =10

i think u interpreted the parantheses wrong. just observe carefully. hope this helps

 

[busdent]

okay, if the problem is like this (your original post)

What is the value of x if (2(5/x+3))^1/2 = 10 ?

a. 3/7
b. 47/5
c. 5/97
d. 2/5
e. 5/47

then (e) is the answer, not -29/10. thus, kaplan was correct.

(2(5/x+3))= (10/x) + 6, so then

(((10/x)+6) ^(1/2))^2 = 10^2

(10/x) + 6=100
10/x= 100-6
10/x=94
10=94x
10/94= x
5/47 = x answer

10/2= 5
94/2=47

hope this helps. your edit problem is different from the first problem. but your answer was correct for the new problem.
your new problem is this after multiplication
(10/(x+3))^(1/2) = 10

which is not the same as

((10/x) + 6)^(1/2) =10

i think u interpreted the parantheses wrong. just observe carefully. hope this helps

Ya my edited one should be the write post. I uploaded a pic. see that and let me know what you think. Sorry the pic came bad cuz I am sitting in the library and just took one with my phone.

 

[caminito]

i couldn't see the problem clearly so i couldn't conclude it. however, the best way to check if 5/47 is the answer for x or not is to plug in that answer for x and see if the answer turns out to be 10 when all operations are carried out correctly. if not, then the answer is not 5/47 and the problem is wrong.

 

[caminito]

it is i again. if u were sure that your second post for the problem was correct, then your answer -29/10 was correct and kaplan was wrong. u just got to believe yourself, okay?

 

[busdent]

thanks caminito