3(y-5)-2(y-4)
-5(5-x)-4x
1/3(3x-6)-2/7(7x-21)
5,4(3y-2)-7,2(2y-3)

3(y-5)-2(y-4)=3у-15-2у+8=у-7;
-5(5-x)-4x=-25+5х-4х=х-25;
1/3(3x-6)-2/7(7x-21)=х-2-2х+6=4-х;
5,4(3y-2)-7,2(2y-3)=16,2у- 10,8-14,4у+21,6=1,8у-10,8