3(2-3х) (-1)+7(4-2х)=12
6-9x+1+28-14x=12 35-23x=12 -23x=-23 x=1
3(2-3x)(-1)+7(4-2x)=12 (6-9x) (-1)+28-14x=12 -6+9x+28-14x=12 -5x=12-28+6 -5x=-10 x=2