how to factor 7a^2+44ab-35b^2
please explain
7a^2+44ab-35b^2
we need to find 2 numbers whose sum = 44 and product = 7 * (-35) = 7 * 7 * (-5)
we get by inspection 49 and - 5
so 7a^2+44ab-35b^2 = 7a^2+49ab-5ab - 35b^2
= 7a(a+7b) -5b(a+7b) = (a+7b)(7a- 5b)
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7a^2+44ab-35b^2
we need to find 2 numbers whose sum = 44 and product = 7 * (-35) = 7 * 7 * (-5)
we get by inspection 49 and - 5
so 7a^2+44ab-35b^2 = 7a^2+49ab-5ab - 35b^2
= 7a(a+7b) -5b(a+7b) = (a+7b)(7a- 5b)