Question

x + 3 [2x+3(x+40] =20

Answer 1

x + 3 [2x+3(x+40] =20
x + 3 [2x+3x+120] =20
x + 3 [5x+120] =20
x + 15x+360=20
16x+360=20
16x=20-360
16x= -340
x=-340/16
x= -21,25

Answer 2

Olá, boa noite ☺

Resolução:

X + 3[2x+3(x+40)] =20

x + 3[2x + 3x + 120] = 20.

x + 6x + 9x + 360 = 20.

16x= 20 - 360.

16x=-340.

x=-340/16 :  4/4 = -85/4.

x= -85/4.

Bons estudos :)