Решите уравнения:

1) x-2/6 + x/2 = 5x-2/9;
2) 5+2x/3 = x-3/5 + x+5/2;
3) 3(x+1)/8 + 2(5-x)/3 = 16-13x;
4) 5(7-2x)/3 - 4x-2/9 = x-19/2.