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 Post subject: Algebra Book IV - Q. #42, 44, 47, 50
PostPosted: Wed May 23, 2012 7:32 pm 
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Joined: Wed May 23, 2012 7:13 pm
Posts: 2
Hi,

Can you please explain the best approach for the following question above?

#42 - coming up with 1/9
#44 - 5 1/x(5x radical 125), how did the 5 disappear in the explanation
#47
#50 - I originally came up with the answer -4 & 1 by factoring. How do you know which approach to use - factoring, sub?

Thank you..


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 Post subject: Re: Algebra Book IV - Q. #42, 44, 47, 50
PostPosted: Thu May 24, 2012 10:03 pm 
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Joined: Wed May 23, 2012 7:13 pm
Posts: 2
nevermind on problem 44 & 50. I figured those out.


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 Post subject: Re: Algebra Book IV - Q. #42, 44, 47, 50
PostPosted: Sun May 27, 2012 6:48 am 
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Joined: Thu Feb 12, 2009 6:32 pm
Posts: 497
#42

start from the inside and work your way out

512 = 2^9

(2^9)^(1/3) = 2^3

(2^3)^(1/2) = 2^(3/2)

(2^(3/2))^(1/3) = 2^(1/2)

(2^(1/2))^2 = 2


#47


x/(x+y) = 6

x = 6(x+y)

x = 6x + 6y

-5x = 6y

x = -(6/5)y

y/(y + x) = y / (y -(6/5)y)

= 1/ ( 1 - 6/5)

= 1/(5/5 - 6/5)

= 1/(-1/5)

= - 5


- Veritas Help


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 Post subject: Re: Algebra Book IV - Q. #42, 44, 47, 50
PostPosted: Mon Jun 18, 2012 8:45 pm 
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Joined: Mon Jun 18, 2012 8:40 pm
Posts: 2
How did you get from

y/(y + x) = y / (y -(6/5)y)

to

= 1/ ( 1 - 6/5)

??


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 Post subject: Re: Algebra Book IV - Q. #42, 44, 47, 50
PostPosted: Tue Jun 19, 2012 5:36 pm 
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Joined: Thu Feb 12, 2009 6:32 pm
Posts: 497
divide each term by y

y/y = 1

Veritas Help


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