4(3y-1)-3(y-1)>2(3+y)
12у-4-3у+3>6+2у
9у-2у>6+1
7у>7
У>7/7
У>1
2х - 7 = х + 3
2х - х = 3 + 7
х = 10
проверка:
2 * 10 - 7 = 10 + 3
20 - 7 = 13
13 = 13
Х²-3х-1/2=х-1
х²-3х-х-0,5+1=0
х²-4х+0,5=0
D = 16-2=14
х= (4+√14)/2 или х= (4-√14)/2
69-(y-28)=13
y-28=69-13
y-28=56
y=56+28
y=84
69-(84-28)=13
13=13