Ответ:
8) 5/6x + 16 = 4/9x + 9x │*18
15x+288 = 8x+162x
15x-8x-162x = -288
-155x = -288
x = 1 133/155
9) (x + 2 1/3)1/7 = 9/14x - 1/6
1/7x + 1/3 = 9/14x - 1/6 │*42
6x+14 = 18x-7
6x-18x = -7-14
-12x = -21
x = 1.75
10) (x-3)/4 = (4+x)/5 │*20
5(x-3) = 4(4+x)
5x-15 = 16+4x
5x-4x = 16+15
x = 31