А)2x=4/7;б)-10z=2/5;в)3x=-1/3;г)-5y=-2(две целых)1/2;д)-1/3x=4;е)4/5z=-20;ж)1/4x=1/2;з)2/9y=0; и)-2/7z=-2/7;к)2x=-1/3;л)1/8y=4; м)-6u=2/3;

1) 2 х = 4/7.

х = 4/7 : 2/1.

х = 4/7 * 1/2.

х = 4/14.

2) - 10 z = 2/5.

 z = 2/5 : (- 10/1).

z = 2/5 * (- 1/10).

z = - 2/50 = - 1/25.

3) 3 х = - 1/3.

х = - 1/3 : 3/1.

х = - 1/3 * 1/3.

х = - 1/9.

4) - 5 у = 2 1/2.

5 у = 2 1/2.

у = 5/2 : 5/1.

у = 5/2 * 1/5.

у = 5/10 = 1/2 = 0,5.

5) - 1/3 х = 4.

х = 4/1 : (- 1/3).

х = 4/1 * (- 3/1).

х = - 12/1 = - 12.

6) 4/5 z = - 20.

z = - 20/1 : 4/5.

z = - 20/1 * 5/4.

z = - 100/4 = - 25.

7) 1/4 х = 1/2.

х = 1/2 : 1/4.

х = 1/2 * 4/1.

х = 4/2 = 2.

8) 2/9 у = 0.

у = 0 : 2/9.

у = 0 * 9/2.

у = 0.

9) - 2/7 z = - 2/7.

z = 2/7 : 2/7.

z = 2/7 * 7/2.

z = 14/14 = 1.

10) 2 х = - 1/3.

х = - 1/3 : 2/1.

х = - 1/3 * 1/2.

х = - 1/6.

11) 1/8 у = 4.

у = 4/1 : 1/8.

у = 4/1 * 8/1.

у = 32/1 = 32.

12) - 6 u = 2/3.

u = 2/3 : (- 6/1).

u = 2/3 * (- 1/6).

u = - 2/18 = - 1/9.