SOLUTION: Factor by grouping 18a^3 - 24a^2b + 15ab^2 - 20b^3

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Question 68786: Factor by grouping
18a^3 - 24a^2b + 15ab^2 - 20b^3
Answer by rmromero(383) About Me  (Show Source):
You can put this solution on YOUR website!
18a%5E3+-+24a%5E2b+%2B+15ab%5E2+-+20b%5E3
 
  = %2818a%5E3+-+24a%5E2b%29+%2B+%2815ab%5E2+-+20b%5E3%29

Find the common factor :
  = %2818a%5E3+-+24a%5E2b%29+%2B+%2815ab%5E2+-+20b%5E3%29

  = 6a%5E2%283a+-+4b%29+%2B+5b%5E2%283a+-+4b%29

Notice that 3a - 4b is a common factor to both terms.
The distributive property can be used to factor out 3a - 4b

  = highlight+%28%286a%5E2+%2B+5b%5E2%29%283a+-+4b%29%29