2 1 - (х-5)+1 - (х+1)=9 3 3

21 - (х - 5) + 1 - (х + 1) = 933;

21 – х + 5 + 1 – х – 1 = 933;

- 2х = 933 – 21 – 5 + 1 - 1;

- 2х = 933 – 26 + 1 - 1;

- 2х = 907;

- х = 907 / 2;

х = - 453,5.

Проверяем:

21 - ((-453,5) -5) + 1 - ((-453,5) +1) = 933;

21 + 453,5 + 5 + 1 + 453,5 – 1 = 933;

933 = 933.