Question

Помогите решить эти все упражнения. Надеюсь на вашу помощь. Заранее спасибо.

Answer 1

$1) - 200 \times ( - 50 + 20) = - 200 \times ( - 30) = 6000 \\ 2) - 250 \times ( - 70 + 50) = - 250 \times ( - 20) = 5000 \\ 3) - 250 \times ( - 20 - 30) = - 250 \times ( - 50) = 7500 \\ 4) - 150 \times ( - 30 - 90) = - 150 \times ( - 120) = 18000$

$5) - 400 \times ( - 60 + 50) = - 400 \times ( - 10) = 4000 \\ 6) - 250 \div ( - 70 + 50) = - 250 \div ( - 20) = 12.5$

$7) - 3600 \div ( - 7 0 + 30) = - 3600 \div ( - 40) =90 \\ 8) - 3200 \div ( - 170 + 250) = - 3200 \div 80 = 40$

$9)- 260 \div ( - 70 - 60) = - 260 \div ( - 130) = 2 \\ 10) - 450 \div (120 - 90) = - 450 \div 30 = - 15$

$a)2x - 10 = - 3 \\ 2x = - 3 + 10 \\ 2x = 7 \\ x = \frac{7}{2} = 3.5 \\ b)9 - 4x = - 9x - 4 \\ 9x - 4x = - 4 - 9 \\ 5x = - 13 \\ x = \frac{ - 13}{5}$

$g)6(5 - 3x) = - 8x - 7 \\ 30 - 18x = - 8x - 7 \\ - 18x + 8x = - 7 - 30 \\ - 10x = - 23 \\ x = \frac{ - 23}{ - 10} = 2.3$

$( \frac{1}{5} + \frac{3}{10} ) \div \frac{1}{2} - 0.6 = ( \frac{1 \times 2 + 3 \times 1}{10} ) \times 2 - 0.6 = \frac{5}{10} \times 2 - 0.6 = \frac{5 \times 2}{10} - 0.6 = \frac{10}{10} - 0.6 = 1 - 0.6 = 0.4$