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avatar+2448 

I actually really need help with this >.< I don't know if i'll even get how to do these after someone has explained them to me. 

 Sep 4, 2018
 #1
avatar+128475 
+2

I assume we want to factor, RP.....so

 

1)  56b^3  + 7b^2  + 168b  + 21

 

We need to do something called "factor by  grouping"....there isn't a standard proceedure, necessarily, but here's one way we can proceed

 

Take the GCF  out of 56b^3  + 7b^2  =    7b^2

Take the GCF out of 168b + 21   =  21

Write the expression back like this :

 

7b^2 (8b + 1)   + 21 (8b + 1)   ......note that  (8b + 1)  is common...so write it...and then follow it with the other two terms as a second factor....so we have

 

(8b + 1) ( 7b^2 + 21)   .....note....in the second factor, we can take out a "7"...so we have...

 

(8b + 1) (b^2 + 3) *7  =

 

7(8b + 1) (b^2 + 3)

 

 

cool cool cool

 Sep 4, 2018
 #2
avatar+128475 
+2

2)   294n^3  + 343n^2  + 126n  + 147

 

This one isn't as obvious....

 

Take out the GCF between 294n^3  and 343n^2   =  49n^2

Take out the GCF between  126  and 147  = 21

 

So we have

 

49n^2 [ 6n + 7 ]  + 21 [ 6n + 7 ]      

 

[6n + 7 ] [ 49n^2 + 21]      note....in the second factor...we can take out a  "7"  and we have

 

[6n + 7]  [ 7n^2 + 3] *7  

 

7 [ 6n + 7 ] [7n^2 + 3 ] 

 

 

cool cool cool

 Sep 4, 2018
 #3
avatar+2448 
0

Thank you so much for your help, but I still don't understand this >.<

RainbowPanda  Sep 5, 2018

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