Answer:
see explanation
Step-by-step explanation:
To find the roots factor the left side
x³ + 7x² + 12x = 0 ← factor out x from each term
x(x² + 7x + 12) = 0
x(x + 3)(x + 4) = 0
Equate each factor to zero and solve for x
x = 0
x + 3 = 0 ⇒ x = - 3
x + 4 = 0 ⇒ x = - 4
Roots are x = - 4, x = - 3, x = 0
