How do you factor $a^2b + 2ab - 15b$ ?

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Answer 1 · 2018-03-26T12:15:15

$b(a+5)(a-3)$

First factor $b$ from every term

$b(a^2+2a-15)$

Then factorize the quadratic knowing that the factors of 15 are 15,1 and 3,5. The last two sum to 2 (5-3) so this is the correct pair

$b(a+5)(a-3)$

How do you factor a^2b + 2ab - 15ba^2b + 2ab - 15b?