Question

помогите пожалуйста решить
буду очень благодарна)​

Answer 1

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

Ответ:

x = 14

b = 1.8

Answer 2

$\left \{ {x-5b=5}|\cdot(-2) \atop {4x-10b=38}} \right.\\\\+\left \{ {-2x+10b=-10} \atop {4x-10b=38}} \right.\\--------\\2x=28\\\\x=14\\\\5b=x-5=14-5=9\\\\b=9:5=1,8\\\\Otvet:\boxed{x=14 \ ; \ b=1,8}$