1) 4а*(-3в)=-12ав
8(2х-3)=16х-24
(4-х)*(-3)=12+3х
2)
х+5+(4х-6)=Х+5+4Х-6=5Х-1
(3х-2)-(5х-8)=3х-2-5х+8=6-2х
20+5(0.2у-4)=20+у-20=у
3)
2(а-4)-(1-2а)=2а-8-1+2а=4а-9 , а=-1.5
4*(-1.5)-9=-6-9=-15
4)
8(2у-5)-4(3у-10)-4у=0
16у-40-12у+40-4у=0
0=0
5)
z-(y+(z-t))=z-(y+z-t)=z-y-z+t=t-y