(c + 2958): 57=139
с+2958=139*57
с+2958=7923
с=7923-2958
с=4965
Проверка:
(4965+2958):57=139
139=139
A) 7(у+3)-(у+2)>2(5y+1)
7y+21-2y+4>109y+2
5y-10y>2-25
-5y>-23
y<23/5
y<4,6
b) 6(3+5y)-(2+7y)<5(4+3y)
18+30y-2-7y<20+15t
23y-15y<20+2-18
8y<4
y<8/4
y<1/2
y<0.5
d)4(3y-1)-3(y-1)>2(3+y)
12y-4-3y+3>6+2y
9y-2y>6+1
7y>7
y>7
4) 28/32..................
1,5(4a-3)-5(b+2) = 6a-4,5-5b-10=6a-5b-14,5