\(3x+12=36\)

\(\Leftrightarrow3x=36-12\)

\(\Leftrightarrow3x=24\)

\(\Leftrightarrow x=24\div3\)

\(\Leftrightarrow x=8\)

\(4x+28=134\)

\(\Leftrightarrow4x=134-28\)

\(\Leftrightarrow4x=106\)

\(\Leftrightarrow x=106\div4\)

\(\Leftrightarrow x=\frac{53}{2}\)

\(5x-22=-17\)

\(\Leftrightarrow5x=22-17\)

\(\Leftrightarrow5x=5\)

\(\Leftrightarrow x=5\div5\)

\(\Leftrightarrow x=1\)

3x + 12 = 36 

3x = 36 - 12

3x = 24

x = 8

4x + 28 = 134

4x = 134 - 28

4x = 106

x = 106 : 4

x = 26 , 5

5x - 22 = -17

5x = -17 + 22

5x = 5

x = 1

3x - 184 = -49

3x = -49 + 184

3x = 135

x = 135 : 3  = 45

4x + 12 = 56

4x = 56 - 12

4x = 44

x = 11

3x - 127 = - 22

3x = -22 + 127 

3x = 105

x = 105 : 3 = 35

3x + 22 = 124

3x = 124 - 22 = 102

x = 102 : 3

x = 34

4x - 9 = 31

4x = 31 + 9 = 40

x = 40 : 4= 10

5x - 211 = -31 

5x = -31 + 211

5x = 180

x = 180 : 5

x  = 36

2) 3x + 12 = 36

    3x         =36-12

    3x         =24

     x          =24 :3

      x          =8

tìm x 

67 - 3x = 31

=> 3x =    36

=> x = 12           ,                

18 + 3x =24

=> 3x = 6

=> x = 2

( x - 36 ) : 18 = 12    

=> x - 36 = 216

=> x = 252

 ,                ( x + 74 ) - 318 = 200

=> x + 74 =  518

=> x = 444

3636 : ( 12x - 91 ) = 36       ,

=> 12x - 91 = 101

=> 12x = 192

=> x  = 16

( x : 23 + 45 ) x 67 = 8911

=> x : 23  + 45 = 133

=> x : 23 = 88

=> x = 2024

Tìm x

67 - 3x = 31

=> 3x = 67 - 31

=> 3x = 46

=> x = 46/3

18 + 3x = 24

=> 3x = 24 - 18

=> 3x = 6

=> x = 2

(x - 36) : 18 = 12

x - 36 = 12.18

x - 36 = 216

x = 216 + 36

x = 252

(x + 74) - 318 = 200

x + 74 = 200 + 318

x + 74 = 518

x = 518 - 74

x = 444

3636 : (12x - 91) = 36

12x - 91 = 3636 : 36

12x - 91 = 101

12x = 101 + 91

12x = 192

x = 16

(x : 23 + 45) x 67 = 8911

x : 23 + 45 = 8911 : 67

x : 23 + 45 = 133

x : 23 = 133 + 45

x : 23 = 178

x = 4094

\(67-3x=31\)

\(3x=36\)

\(x=12\)

\(18+3x=24\)

\(3x=6\)

\(x=2\)

\(\left(x-36\right):18=12\)

\(x-36=216\)

\(x=252\)

\(\left(x+74\right)-318=200\)

\(x+74=518\)

\(x=444\)

\(3636:\left(12x-91\right)=36\)

\(12x-91=101\)

\(12x=192\)

\(x=12\)

\(\left(\frac{x}{23}+45\right).67=8911\)

\(\frac{x}{23}+45=133\)

\(\frac{x}{23}=88\)

\(\Rightarrow\frac{x}{23}=\frac{2024}{23}\)

\(\Rightarrow x=2024\)

A)13-5x=3

         5x=13-3

         5x=10

          x=10:5

          x=2

B)2(3x-5)-36=42

   2(3x-5)      =42+36

  2(3x-5)        =78

     3x-5          =78:2

      3x-5        =39

      3x           =39+5

      3x           =44

        x           =44:3

        x           =44/3

C)27:(x-31)=9

         x-31  =27:9

         x-31  =3

         x       =3+31

         x        =34

Bn k cho mik nha!!!!!

a) 13 - 5x = 3

5x = 10

x = 2

b) 2(3x - 5) - 36 = 42

   6x - 10 - 36 = 42

    6x = 42 + 10 + 36

  6x = 88

 x = 88/6 = 44/3

c) 27 : ( x-31)=9

     x - 31 = 27 : 9

  x - 31 = 3

   x = 31 + 3 = 34

\(\Leftrightarrow\frac{3x+1}{17}+\frac{3x+1}{19}+\frac{3x+1}{23}-\frac{3x+1}{29}-\frac{3x+1}{31}=0\)

\(\Leftrightarrow\left(3x+1\right)\left(\frac{1}{17}+\frac{1}{19}+\frac{1}{23}-\frac{1}{29}-\frac{1}{31}\right)=0\)

\(\Leftrightarrow3x+1=0\) ( vì \(\frac{1}{17}+\frac{1}{19}+\frac{1}{23}-\frac{1}{29}-\frac{1}{31}\ne0\))

\(\Leftrightarrow3x=-1\)

\(\Leftrightarrow x=-\frac{1}{3}\)

\(\frac{3x+1}{17}+\frac{3x+1}{19}+\frac{3x+1}{23}=\frac{3x+1}{29}+\frac{3x+1}{31}\)

\(\Rightarrow\frac{3x+1}{17}+\frac{3x+1}{19}+\frac{3x+1}{23}-\frac{3x+1}{29}-\frac{3x+1}{31}=0\)

\(\Rightarrow\left(3x+1\right)\left(\frac{1}{17}+\frac{1}{19}+\frac{1}{23}-\frac{1}{29}-\frac{1}{31}\right)=0\)

Mà \(\frac{1}{17}+\frac{1}{19}+\frac{1}{23}-\frac{1}{29}-\frac{1}{31}\ne0\)

\(\Rightarrow3x+1=0\)

\(\Rightarrow x=-\frac{1}{3}\)

\(\frac{3x+1}{17}+\frac{3x+1}{19}+\frac{3x+1}{23}=\frac{3x+1}{29}+\frac{3x+1}{31}\)

\(\Rightarrow\frac{3x+1}{17}+\frac{3x+1}{19}+\frac{3x+1}{23}-\frac{3x+1}{29}-\frac{3x+1}{31}=0\)

\(\Rightarrow\left(3x+1\right)\left(\frac{1}{17}+\frac{1}{19}+\frac{1}{23}-\frac{1}{29}-\frac{1}{31}\right)=0\)

=>3x+1=0

=>x=-1/3

\(3x^2-3x\left(-2+x\right)=36\)

\(\Leftrightarrow3x^2+6x-3x^2-36=0\)

\(\Leftrightarrow6x-36=0\)

\(\Leftrightarrow x=6\)

1, => [ 462 + 642 - 2x ] : 2 = 531

1104 -2x = 1062

2x = 42

x =21

2,  ≫ [ 982 -2x -166 ] : 2 =336

816 - 2x = 672

2x=144

x=72