1.2x-10.3x=15 2.0.52x-(1-0.52)x=80 3.x/2+3x/2=7 4.3x+7=32-2x 5.3x+5(138-x)=540 6.3x-7(x-1)=3-2(x+3) 7.18x+3x-3=18-2(2x-1) 8.3(20-y)=6y-4(y-11) 9.-(x/4-1)=5 10.7(2x-1)-3(4x-1)=4(3x+2)-1; 11.(5y+1)+ (1-...