1)2/9 x=5/12
x=5/12 :2/9=5/12*9/2=15/8=1 7/8
2)4/15 y=2/5
y=2/5: 4/15=2/5*15/4=6/4=1 2/4=1 1/2=1.5
3)3/5 x=6
x=6:3/5=6*5/3=10
4)7/8 y =14
y=14:7/8=14*8/7=16
5)3/7 x= 1 4/5
3/7 x= 9/5
x=9/5:3/7=9/5*7/3=21/5=4 1/5=4.2
6)9/10 y=4 1/2
9/10 y= 9/2
y=9/2:9/10=9/2*10/9=5
2 - 3(4х - 9) ≥ 7х - 4(3х + 5)
2 - 12х + 27 ≥ 7х - 12х - 20
- 12х + 12х - 7х ≥ - 20 - 2 - 27
- 7х ≥ - 49
х ≤ 7
Ответ; (- ∞;7 ]
Нет не верно
(12-6)-2=12-(6-2)
12-6-2=12-6-(-2)
12-6-2=12-6+2
4≠8
4; 0; 10; 0. Are you serious?