Question

Решите пожалуйста 4 5 и 6 пжж

Answer 1

4)
$( - 1 \frac{3}{14} - \frac{8}{21} + \frac{1}{6}) \times 0.7 + 0.3 = ( - \frac{17}{14} - \frac{8}{21} + \frac{1}{6} ) \times \frac{7}{10} + \frac{3}{10} = ( - \frac{51}{42} - \frac{16}{42} + \frac{7}{42} ) \times \frac{7}{10} + \frac{3}{10} = \frac{ - 60}{42} \times \frac{7}{10} + \frac{3}{10} = - 1 + \frac{3}{10} = - \frac{7}{10} = - 0.7$
Ответ: -0,7.

5)
$0.1x - y = 1 \\ 0.3x + y = 3 \\ \\ 0.4x = 4 \\ y = 0.1x - 1 \\ \\ x = 10 \\ y = 0$
Ответ: (10; 0)

6)
$\frac{1}{2}x < 16 - \frac{3}{2} x \\ \frac{1}{2} x + \frac{3}{2} x < 16 \\ 2x < 16 \\ x < 8$
=> x € (-беск; 8)