Ответ:

6)

[tex]\frac{x}{3}-\frac{x}{2} +\frac{x}{6} = \frac{2x}{6}-\frac{3x}{6}+ \frac{x}{6} = \frac{2x-3x+x}{6} = \frac{0*x}{6} =0[/tex]

7)

0.83y+0.56y-0.92y-0.83y = 0.56y-0.92y = -0.36y

8)

[tex]\frac{5}{6}z-1\frac{3}{4}z+\frac{13}{18} z = \frac{5}{6}z-1\frac{3}{4}z+\frac{13}{18} z =\frac{15}{18}z-1\frac{}{4}z+\frac{13}{18} z = \frac{28}{18}z-1\frac{3}{4} z = 1\frac{10}{18} z- 1\frac{3}{4} z =\frac{5}{9}z -\frac{3}{4} z = \frac{20}{36}z-\frac{27}{36} z=-\frac{7}{36} z[/tex]