1) 1 1/2 - (5/6х + 1/3) = 8/9
3/2 - 5/6х + 1/3 = 8/9
3\2 + 1/3 -5/6х = 8/9
11/6 - 5/6х = 8/9
5/6х = 11/9 - 8/9
5/6х = 1/3
х= 1/3 : 5/6
х= 1/3 * 6/5
х= 2/5
2) 5\8у - 1/2у + 1\12у = 1/4
1/8у + 1\12у = 1/4
5/24у= 1/4
у= 1/4 : 5/24
у= 1/4 * 24/5
у= 1 1/5
3) 4/5z + 5/6z +1/2 = 1 3/5
49/30z + 1/2 = 8/5
49/30z = 8/5 - 1/2
49/30z = 11/10
z = 11/10 :49/30
z= 11/10 * 30/49
z= 33/49