Ответ:

1) 13t-8(3t-2)=-7t-5(12-3t)

13t-24t+16=-7t-60+15t

13t-24t+7t-15t=-60-16

-19t=-76

t=4

2) 7(2u-1)-6(11-u)=3(u+4)

14u-7-66+6u=3u+12

14u+6u-3u=12+7+66

17u=85

u=5

3) 2(2t+3)=8(1-t)-5(t-2)

4t+6=8-8t-5t+10

4t+8t+5t=8+10-6

17t=12

t=12/17

4) 17(2-3u)-5(u+12)=8(1-7u)

34-51u-5u-60=8-56u

-51u-5u+56u=8+60-34

∅