решить
буду очень благодарна)​

x - 5b = 5

4x - 10b = 38

x = 5 + 5b

4x - 10b = 38

Сделаем замену:

x = 5 + 5b

4*(5 + 5b) - 10b = 38

x = 5 + 5b

20 + 20b - 10b = 38

x = 5 + 5b

10b = 38 - 20

x = 5 + 5b

10b = 18

x = 5 + 5b

b = 1.8

x = 5 + 5*1.8

b = 1.8

x = 14

b = 1.8

x = 14

b = 1.8