Question

Допоможіть дуже сильно прошу

Answer 1

Ответ:

1.

1) 5

2) 57

3) -12

2.

-0,4

Answer 2

1.

1)

$- 2 - ( - 7) = - 2 + 7 = 5$

2)

$- 5.7 \times ( - 10) = 57$

3)

$2.4 \div ( - 0.2) = - 12$

2.

$\frac{13.6 - 14.1 - 3.4}{3} = - \frac{3.9}{3} = - 1.3$

3.

$\frac{1}{2} (8 - 3 \frac{1}{2} x) = - 1 \frac{1}{4} x - 4 \frac{1}{2} \\ \frac{1}{2} (8 - \frac{7}{2} x) = - \frac{5}{4} x - \frac{9}{2} \\ 4 - \frac{7}{4} x = - \frac{5}{4} x - \frac{9}{2} \\ - \frac{7}{4} x + \frac{5}{4} x = - 4 \frac{1}{2} - 4 \\ - \frac{1}{4} x = - 8 \frac{1}{2} \\ x = \frac{17}{2} \div \frac{1}{4} = \frac{17}{2} \times 4 = 17 \times 2 = 34$

4.

$4( \frac{3}{8} - 3 \frac{1}{4} x) - 15( \frac{2}{3} x - 1 \frac{2}{5} ) - 22.5 = 4( \frac{3}{8} - \frac{13}{4} x) - 15( \frac{2}{3} x - \frac{7}{5} ) - 22.5 = \frac{2}{3} - 13x - 10x + 21 - 22.5 = - 23x + \frac{7}{15}$

При x=-4/23

$- 23 \times ( - \frac{4}{23} ) + \frac{7}{15} = 4 + \frac{7}{15} = 4 \frac{7}{15}$