А)1/2x+3/4=7/16x-5/8 б)2/3-1/6x=7/12x+5/9 в)1/5x+9/10=1/15-3/10x г)7/18-3/4x=5/6x+4/9

А)

1/2x + 3/4 = 7/16x - 5/8
1/2x - 7/16x = -5/8 - 3/4 * 16
8x-7x=-10-12
x = -22

б)
 
2/3 - 1/6x = 7/12x + 5/9
-1/6x - 7/12x = 5/9 - 2/3 * 36
-6x - 21x = 20 - 24;
-27x = 4
x = -4/27

в)

1/5x + 9/10 = 1/15 - 3/10x
1/5x + 3/10x = 1/15 - 9/10 * 30
6x + 9x = 2 - 27
15 x = -25
x = -25/15 = -1 1/3

г) 

7/18 - 3/4x = 5/6x + 4/9
-3/4x - 5/6x = 4/9 - 7/18 * 36
-27x - 30x = 16 - 14
-57x = -2
x = 2/57