Answer:
x = - 20, x = - 3
Explanation:
To find the zeros, let h(x) = 0, that is
x² + 23x + 60 = 0
Consider the factors of the constant term (+ 60) which sum to give the coefficient of the x- term (+ 23)
The factors are + 20 and + 3, since
20 × 3 = 60 and 20 + 3 = 23, thus
(x + 20)(x + 3) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 20 = 0 ⇒ x = - 20
x + 3 = 0 ⇒ x = - 3