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Please help Soon!!

2x^2+13x-7=
 
Or is it prime?

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Vivian L. | Microsoft Word/Excel/Outlook, essay composition, math; I LOVE TO TEACHMicrosoft Word/Excel/Outlook, essay comp...
3.0 3.0 (1 lesson ratings) (1)
1
Hi again David;
2x2+13x-7
For the FOIL...
FIRST must be (2x)(x)=2x2
OUTER and INNER must add-up to 13x
LAST must be (7)(1) or (1)(7) and one number must be negative.
(2x-1)(x+7)
Let's FOIL...
FIRST...(2x)(x)=2x2
OUTER...(2x)(7)=14x
INNER...(-1)(x)=-1x=-x
LAST...(-1)(7)=-7
2x2+14x-x-7
2x2+13x-7

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Parviz F. | Mathematics professor at Community CollegesMathematics professor at Community Colle...
4.8 4.8 (4 lesson ratings) (4)
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 Another way of looking at it.
 
  2 X2 +13X -7
 
  If this is factorable then    
 
there should be 2 integers whose difference is  +13, and product - 14, they are +14, -1
 
2X2 + 14X - X - 7 =2X ( X +7) - ( X + 7 ) = ( 2X - 1 ) ( X + 7)
* ( factoring by group )