Question

Памагите пажалуйста очень быстро нада, дам 35 балов​

Answer 1

1.

х + 2/7 = 3/5

2/7 - 3/5 = -х

10/35 - 21/35 = -х

-х = -11/35

х = 11/35

2.

31/34 - х = 12/40

31/34 - 12/40 = х

31/34 - 3/10 = х

155/170 - 51/170 = х

104/170 = х

х = 52/85

3.

х - 1/5 = 3/21

х = 3/21 + 1/5

х = 1/7 + 1/5

х = 5/35 + 7/35

х = 12/35

4.

6/7 - х = 1/3

6/7 - 1/3 = х

18/21 - 7/21 = х

х = 11/21