Respuesta :

X = 7

Very easy

hope it helped =D
4(x + 9) = 20

1. 4 * x = 4x
    4 * 9 = 36
2. 4x + 36 = 20
    4x + 36-36 = 20 -36
3. 4x = - 16
    4x/4 =- 16/4
4. x = - 4

Answer: x = -4