Первое задание

[tex]1. 6a-6b=6(a-b)\\2. -5c-20d=-5(c+4d)\\3. 3xy+9x=3x(y+3)\\4. -4n-6nm+2np=-2 n (3 m - p + 2)[/tex]

Второе задание

[tex]1. (2x-1)-(1-4x)=2x-1-1+4x=6x-2\overset{x=0.25}{\Rightarrow }6\cdot \frac{1}{4}-2=-\frac{1}{2}\\2. (2-5x)+(6,4x+2,8)=2-5x+6,4x+2,8=1,4 x + 4,8\overset{x=-2,4}{\Rightarrow }\\\Rightarrow -\frac{14}{10}\cdot \frac{24}{10}+\frac{48}{10}=-\frac{7}{5}\cdot \frac{12}{5}+\frac{24}{5}=-\frac{84}{25}+\frac{24}{5}=\frac{-84+120}{25}=\frac{36}{25}[/tex][tex]3. \left (8,5-6,2x \right )-\left ( 4\frac{1}{3}-7\frac{2}{7}x \right )=\frac{85}{10}-\frac{62}{10}x-\frac{13}{3}+\frac{51}{7}x=\\=\frac{17}{2}-\frac{31}{5}x-\frac{13}{3}+\frac{51}{7}x=\frac{51-26}{6}+\frac{-217+255}{35}x=\frac{38}{35}x+\frac{25}{6}\overset{x=35/3}{\Rightarrow }\\\Rightarrow \frac{38}{35}\cdot \frac{35}{3}+\frac{25}{6}=\frac{38}{3}+\frac{25}{6}=\frac{101}{6}[/tex][tex]4. 8x-\left ( 2\frac{5}{7}+4,7x \right )+\left ( 4,7x-6\frac{2}{7} \right )=8x-\left ( \frac{19}{7}+4,7x \right )+4,7x-\frac{44}{7}=\\=8x-\frac{19}{7}-\frac{44}{7}=8x-9\overset{x=-43/8}{\Rightarrow }8\left ( -\frac{43}{8} \right )-9=-43-9=-52[/tex]

Verified answer

Ответ:

Пошаговое объяснение:

№6

1) 6а - 6b = 6(а - b)

2) -5с - 20d = -5(c + 4d)

3) 3xy + 9x = 3x(y + 3)

4) -4n - 6nm + 2np = -2n(2 + 3m - p)

№7

1)

(2х - 1) - (1 - 4х) = 2х - 1 - 1 + 4х = 6х - 2

х = 0,25

6х - 2 = 6 * 0,25 - 2 = 1,5 - 2 = -0,5

2)

(2 - 5х) + (6,4х + 2,8) = 2 - 5х + 6,4х + 2,8 =
1,4х + 4,8

х = -2,4

1,4х + 4,8 = 1,4 * (-2,4) + 4,8 = -3,36 + 4,8 = 1,44

3)

(8,5 - 6,2х) - (4 1/3 - 7 2/7х) =
8 1/2 - 6 2/10х - 4 1/3 + 7 2/7х =
8 3/6 - 6 14/70х - 4 2/6 + 7 20/70х

4 1/6 + 1 6/70х = 4 1/6 + 1 3/35х

х = 11 2/3

4 1/6 + 1 3/35х = 4 1/6 + 1 3/35 * 11 2/3 =
4 1/6 + 38/35 * 35/3 = 4 1/6 + 38/3 =
4 1/6 + 12 2/3 = 4 1/6 + 12 4/6 = 16 5/6

4)

8х - (2 5/7 + 4,7х) + (4,7х - 6 2/7) =
8х - 2 5/7 - 4,7х + 4,7х - 6 2/7 =
8х - 8 7/7 = 8х - 9

х = -5 3/8

8х - 9 = 8 * (-5 3/8) - 9 = 8 * (-43/8) - 9 =
-43 - 9 = -52