3,9 - ( 5,81 - x ) = - 3 3/4
3,9 - 5,81 + x = - 3 3/4
- 1,91 + x = - 3 3/4
x = - 3,75 + 1,91
x = - 1,84
60а-60в+15,1с=60(a-b) +15,1c, если а-в=15,1; c=60
60(a-b) +15,1c = 60*15,1 +15,1*60=2*60*15,1=120*15,1=1812
16,26,36,46,56,66,76,86,96
(63-108):15+4=-45:15+4=-3+4=1