20+3(х-15)
16-4(2+a)
-35-12(b-3)
-18+(4-х)
42-6(7+y)
29-3(t-8)
20+3(х-15)=20+3х-45=3х-25
16-4(2+a)=16-8-4а=8-4а
-35-12(b-3)=-35-12b+36=1-12b
-18+(4-х)=-18+4-х=-14-х
42-6(7+y)=42-42-6у=-6у
29-3(t-8)=29-3t+24=53-3t