Question

помогите пожалуйста​

Answer 1

Ответ:

в)

$\frac{3(0.4x + 1)}{5} = \frac{ - 2(0.3x - 2)}{7}$

$\frac{3(0.4x + 1)}{5} - \frac{ - 2(0.3x - 2)}{7} = 0$

$\frac{1.2x + 3}{5} - \frac{ - 0.6x + 4}{7} = 0$

$\frac{8.4x + 21}{35} - \frac{ - 3x + 20}{35} = 0$

$\frac{8.4x + 21 + 3x - 20}{35} = 0$

$\frac{11.4x - 1}{35} = 0$

$399x - 35 = 0$

$399x = 35$

$x = 11.4$

г)

$0.7x - 2(0.3x + 3) = 3(2x - 1)$

$0.7x - 0.6x - 6 = 6x - 3$

$0.7x - 0.6x - 6x = - 3 + 6$

$- 5.9x = 3$

$- \frac{59}{10} x = 3$

$x = - \frac{30}{59}$