Помогите с заданием 1159

1)3 6/7х-7/9х+4 4/63х=27/7х-7/9х+256/63х=243/63х-49/63х+256/63х=450/63х=7 9/63х=7 1/7х 2)4 2/9у+3 1/5у-2у=38/9у+16/5у-2у=190/45у+144/45у-90/45у=244/45у= =5 19/45у 3)5 3/10х-2 7/100х-2/25х=53/10х-207/100х-2/25х=530/100х-207/100х-8/100х= =315/100х=3 15/100х=3,15х 4)5у-4 3/8у+4/5у=5у-35/8у+4/5у=200/40у-175/40у+32/40у=57/40у=1 17/40у