Question

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

Answer 1

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

Explanation:

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)`