factor the polynomial completely?

Question

y^3+5y^2-9y-45

Answer 1

y^3 + 5y^2 - 9y - 45 can be written as

y^2 (y + 5) - 9 (y + 5)

= (y^2 - 9) ( (y + 5)

= (y + 3) (y - 3) ( y + 5)