3(×+5)-(4-×)-(1+3)×-3

1) 3/5-1/4+1/3=41/603/5-1/4=12/20-5/20=7/207/20+1/3=21/60+20/60=41/60 2) (2/3+1/9)-13/18=1/182/3+1/9=6/9+1/9=7/97/9-13/18=14/18-13/18=1/18 3) 3/4-1/2+7/8=1. 1/83/4-1/2=3/4-2/4=1/41/4+7/8=2/8+7/8=9/8=1  1/8 4) 5/6-2/3+1/4=5/125/6-2/3=5/6-4/6=1/61/6+1/4=2/12+3/12=5/12 5) 1/3-(1/9+1/6)=1/181/9+1/6=2/18+3/18=5/181/3-5/18=6/18-5/18=1/18

3x+15-4+x-x-3x-3 3x+x-x-3x=-15-4+3 0=-16 x= -16:0 x=0