Question

-3 (3b + 1) -12 = 12

Answer 1

-3*(3b + 1) -12 = 12

-9b-3-12=12

-9b= 12+12+3

-9b= 27

b= 27: (-9)

b= -3

Ответ: b= -3

ПРОВЕРКА

-3*(3*(-3)+1)-12=12

12=12