1.4x+2=x+73x=5x=5/32.3-6x-4=2/3-6x=5/3x=-5/183.(4x+2)/6-(5x-1)/6-x+3=6x=-34.4x/(2x+6)+1=7/(2x+6)7-4x=2x+6x=1/6 7(2x-1)-3(4x-1)=4(3x+2)-1; (5y+1)+ (1-y)= (9y+1)+ (1-3y); 20%+(1-20%)(320-x)=320×40% 2(x...