Factories:

6ab – b2 + 12ac – 2bc

6ab – b2 + 12ac – 2bc


= 6ab + 12ac – b2 – 2bc


= (6ab + 12ac) – (b2 + 2bc)


= 6a(b + 2c) – b(b + 2c)


= (b + 2c)(6a – b)


So we get,


6ab – b2 + 12ac – 2bc = (b + 2c)(6a – b)


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