Question 750853
a^2-ab-56b^2


a^2+7ab-8ab-56b^2 ... Note: 7 and -8 both add to -1 and multiply to -56


(a^2+7ab)+(-8ab-56b^2)


a(a+7b)+(-8ab-56b^2)


a(a+7b)-8b(a+7b)


(a-8b)(a+7b)



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a^2-ab-56b^2


completely factors to


(a-8b)(a+7b)