Question

(x+(x+12))*4=600

Answer 1

раскрываем скобки: (х+х+12)*4=600, (2х+12)*4=600,2х+12=150, 2х=150-12=138, х=138:2=69.

Answer 2

х+12=600:4

х+12=150

х=150-12

х=138