180-x=540-6x

=> 6x-x= 540-180

=> 5x= 360

=> x= 72

a ) 100-7(x-5)=58

=> 7(x-5)=42

=.> x-5 = 6

=> x=11

180-5(x+1)=30

=> 5(x+1)=150

=> x+1=30\

=> x=29

6x-5=613

=> 6x=618

=> x=103

a) \(100-7\left(x-5\right)=58\)

\(\Leftrightarrow7\left(x-5\right)=42\)

\(\Leftrightarrow x-5=6\)

\(\Leftrightarrow x=11\)

b) \(180-5\left(x+1\right)=30\)

\(\Leftrightarrow5\left(x+1\right)=150\)

\(\Leftrightarrow x+1=30\)

\(\Leftrightarrow x=29\)

c) \(6x-5=613\)

\(\Leftrightarrow6x=618\)

\(\Leftrightarrow x=103\)

xin lỗi mình mới học lớp 5

Ta có :

6x = 3x+1-5x+6x-5x+4x-9x+7x

=> 6x+1 = (3x+7x) - (5x+5x) + (6x+4x) - 9x

=> 6x+9x+1 = 10x - 10x + 10x

=> 15x+1 = 10x

=> 10x-15x = 1 

=> -5x = 1

=> x = 1 : (-5)

=> x = -1

Vậy x = -1

5x+6x+1=56

<=>5x+6x=56-1

<=>5x+6x=55

<=>x(5+6)=55

<=>x.11=55

<=>x=55:11

<=>x=5

Vậy x=...

6x+1=13

<=>6x=13-1

<=>6x=12

<=>x=12:6

<=>x=2

Vậy x=...

~hok tốt~

k mik nhé

\(5x+6x+1=56\Leftrightarrow5x+6x=56-1\Leftrightarrow5x+6x=55\)

\(\Leftrightarrow\left(5+6\right)x=55\Leftrightarrow11x=55\Leftrightarrow x=55:11\)

\(\Rightarrow x=5\)

\(6x+1=13\Leftrightarrow6x=13-1\Leftrightarrow6x=12\)

\(\Leftrightarrow x=12:6\)

\(\Leftrightarrow x=2\)

q, bạn ghi đề rõ nhé 

s, \(\dfrac{2}{3}x=\dfrac{1}{2}-\dfrac{7}{12}=\dfrac{-1}{12}\Leftrightarrow x=-\dfrac{1}{12}:\dfrac{2}{3}=-\dfrac{3}{24}=-\dfrac{1}{8}\)

t, \(\dfrac{3}{4}x=\dfrac{1}{6}-\dfrac{1}{5}=\dfrac{-1}{30}\Leftrightarrow x=-\dfrac{1}{30}:\dfrac{3}{4}=-\dfrac{4}{90}=-\dfrac{2}{45}\)

u, \(\dfrac{1}{6}x=\dfrac{3}{8}-\dfrac{1}{4}=\dfrac{1}{8}\Leftrightarrow x=\dfrac{1}{8}:\dfrac{1}{6}=\dfrac{6}{8}=\dfrac{3}{4}\)

s, 

t, 

u,