Respuesta :

Answer:

x² + 4x + 3

Step-by-step explanation:

Given

(x + 1)(x + 3)

Each term in the second factor is multiplied by each term in the first factor, that is

x(x + 3) + 1(x + 3) ← distribute both parenthesis

= x² + 3x + x + 3 ← collect like terms

= x² + 4x + 3