функция задана формулой y=5x-10                                              _______

у = (5х-10) / 3

1) у = 2/3                                                 2) у = 3 1/3

2/3 = (5х-10)/3                                            10/3 = (5х-10)/3

Решаем крест на крест                               Решаем крест на крест                              

6 = 3(5х-10)                                                 30 = 3(5х-10)

6 = 15х-30                                                   30 = 15х-30

15х = 36                                                      15х = 60

 х = 2,4                                                        х = 4