1) 5/9 =15/27 = 25/40 =4072
2) 7/6 = 21/18 =35/30 = 49/42
3) 3/4 = 18/24 = 24/32 = 36/48
4) 2/3 = 10/15 = 14/21 = 18/27
7- Х/3 = Х+ 8
-Х/3= Х + 8 -7
-Х/3 - Х = 1
- 1 1/3 • Х = 1
-(1•3+1)/3• Х = 1
- 4/3•Х= 1
Х= 1 : (-4/3)
Х= 1• (-3/4)
Х= -3/4 = -0,75 Ответ
Проверка
7- Х/3= Х + 8
7- ((-0,75)/3)= -0,75+8
7+ 0,75/3= 8- 0,75
7+ 0,25= 7,25
7,25=7,25