Question

Find all roots: x^3 + 7x^2 + 12x = 0
Show all work and check your answer.

Answer 1

Answer:

$x=0,x=-4,x=-3$

Step-by-step explanation:

The given equation is

$x^3 + 7x^2 + 12x = 0$

Factoring by x:

$(x^2 + 7x + 12)x = 0$

One of the root is x=0. Let's solve the parentheses.

Expanding the trinomial

$x^2 + 4x+3x + 12=0$

Factoring

$x(x + 4)+3(x + 4)=0$

Factoring

$(x + 4)(x+3)=0$

This will give us the two remaining roots

$x=-4,x=-3$