There are two zeros: -3 and -1. This is because when you factor f(x)= x^2 + 4x + 3, it becomes f(x) = (x + 3)(x + 1). In order to find the zeros, set f(x) to 0, and then solve for x for both (x + 3) and (x + 1). You can check your answer by substituting either -3 or -1 for x in the equation 0 = x^2 + 4x + 3.
