Respuesta :

Answer:

x = 6

Step-by-step explanation:

f(x) = 2(x + 4)

Let f(x) =20

20 =  2(x + 4)

Divide by 2

20/2 = 2/2 (x+4)

10 = x+4

Subtract 4 from each side

10-4 =x+4-4

6 =x