А)(4•b-16):2=10
(4•b-16)=10•2
(4•b-16)=20
4•b=20+16
4•b=36
b=36:4
b=9
Б)(2+x:7)•8=72
(2+x:7)=72:8
(2+x:7)=9
x:7=9-2
x:7=7
x=7•7
x=49
В)35:(15-y:8)=5
(15-y:8)=35:5
(15-y:8)=7
y:8=15-7
y:8=8
y=8•8
y=64
Г)(t•3+5):4=8
(t•3+5)=8•4
(t•3+5)=32
t•3=32-5
t•3=27
t=27:3
t=9