4 5 и 6 №620(срочно) прошу вас))))

2(х+3)=30
2х+6=30
2х=24
х=12

25х/10  *1/14 = 1/7 * 1/30
25х/140 = 1/210
25х= 140/210=2/3
х=2/75

36/35 = 12х/5
12х= 936*5 0/35
12х=36/7
х=36/84=3/7

2/5 = 6/(x+3)
2(x+3) = 6*5
2x+6 = 30
2x = 30 - 6
x = 24/2 = 12

5/6 = 15/(2x-3)
5(2x-3)=15*6
10x-15=90
10x=90-15
x=75/10=7 1/2

12 : 4x/5 = 20 : 1/4
12 * 5x/4 = 20 * 4
15x = 80
x = 80/15 = 5 1/3