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Write out the steps so I can take notes, please!! I need to study before my next quiz ^.^

 Sep 12, 2019
 #1
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   x                 20                             2

___  =       ___________   +    _______

x - 4          (x + 4) ( x - 1)             x  - 1

 

Multiply through by the common denominator   ( x - 4) ( x + 4) ( x - 1)    and we have

 

x (x + 4) ( x - 1)  =  20 (x - 4)  +  2 (x - 4) (x + 4)      simplify

 

x ( x^2 + 3x - 4)  =  20x - 80 + 2( x^2 - 16)

 

x^3 + 3x^2 - 4x   =  20x - 80  + 2x^2 - 32

 

x^3 + x^2 - 24x + 112 =  0    

 

WolframAlpha shows that the only real solution  is   x  ≈ -6.8684

 

https://www.wolframalpha.com/input/?i=x%5E3+%2B+x%5E2+-+24x+%2B+112++%3D++0

 

 

cool cool cool

 Sep 12, 2019
 #2
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Thanks so much!! 

Guest Sep 12, 2019

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