1.2x+3x+4x=189x=18x=22.13x-15x+x=-3-x=-3x=33.2.5y+10y-6y=15-21.56.5y=-6.5y=-14.1/2b-2/3b+b=2/3*6-11/2b-2/3b+b=37/6b=3b=18/75.x+3x=-164x=-16x=-46.16y-2.5y-7.5y=56y=5y=5/67.3x+5=4x-1-x=-6x=68.9-3y=5y+5-...