Respuesta :

Answer:

x = 7, x = -3

Step-by-step explanation:

We can find the zeros by factoring the equation using the zero product property.

x^2-4x-21 = 0

(x-7)(x+3) = 0

x-7 = 0

x = 7

x+3 = 0

x = -3

Zeros are x=7 and x= -3.