Ответ:

1) 7х /6 =49/14

7х ×14 = 6 × 49

98х = 294

Х = 294 :98

Х = 3

2) 2/15 =3/5х

2×5х =15 ×3

10х = 45

Х = 4,5

3) 8/13= 2х/39

8×39=13×2х

312 =26х

Х = 312:26

Х = 12

4) 2/3 =28/7х

2×7х = 3×28

14х = 84

Х= 6

5) 3/14 = 21/ 2( х+31)

14×21= 3× (2х+62)

294 = 6х +186

6х =294 -186

6х = 108

Х = 18

6) 9/10 =63/5(х+8)

10×63= 9 (5х +40)

630 = 45х +360

45х = 630 -360

45х = 270

Х = 6

Пошаговое объяснение: