Question 198245
24 -4a +6b -ab
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This  factoring  is  called  grouping,  and  is  possibly  the  hardest  type
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4 ( 6-a)  + b ( 6-a)
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(4+b)  (6-a)
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checking  FOIL  answer,  24 -4a +6b -ab
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review  carefully,,,usually  the  next  to  last  step  is  hardest  to  visualize,  but  try
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a c  +b c  = (a+b) (c) ,  above    c   is  just  (6-a)