1: x=3/4-1/2=3/4-2/4=1/4

2: x-1/5=2/11

=>x=2/11+1/5=21/55

3: x-5/6=16/42-8/56

=>x-5/6=8/21-4/28=5/21

=>x=5/21+5/6=15/14

4: x/5=5/6-19/30

=>x/5=25/30-19/30=6/30=1/5

=>x=1

5: =>|x|=1/3+1/4=7/12

=>x=7/12 hoặc x=-7/12

6: x=-1/2+3/4

=>x=3/4-1/2=1/4

11: x-(-6/12)=9/48

=>x+1/2=3/16

=>x=3/16-1/2=-5/16

1)x= 1/4

2)x= 2/11+ 1/5

   x= 21/55

3)x - 5/6 = 5/21

   x         = 5/21+5/6

   x         = 15/14

4)x/5 = 5/6 + -19/30

   x:5 = 1/5

   x    = 1/5.5

   x    = 1

5) |x| - 1/4 = 6/18

    |x|           = 6/18 - 1/4

    |x|            =7/12

⇒x= 7/12 hoặc -7/12

6)x = -1/2 +3/4

   x= 1/4

7) x/15 = 3/5 + -2/3

   x:15  = -1/15

  x        = -1/15. 15

  x        = -1

8)11/8 + 13/6 = 85/x  

       85/24      = 85/x

  ⇒      x           = 24

9) x - 7/8 = 13/12

   x          = 13/12 + 7/8

   x          = 47/24

10)x - -6/15 = 4/27  

     x            = 4/27 + (-6/15)

    x             = -34/135

11) -(-6/12)+x = 9/48

                    x= 9/48 - 6/12

                    x = -5/16

12) x - 4/6 = 5/25 + -7/15

      x -4/6  =  -4/15

     x           = -4/15 + 4/6

    x             = 2/5

Bài 1:

a: \(x=\dfrac{2}{3}:\dfrac{3}{5}=\dfrac{2}{3}\cdot\dfrac{5}{3}=\dfrac{10}{9}\)

b: \(x=\dfrac{17}{8}:\dfrac{7}{17}=\dfrac{17}{8}\cdot\dfrac{17}{7}=\dfrac{289}{56}\)

c: \(x=-\dfrac{3}{4}:\dfrac{7}{12}=\dfrac{-3}{4}\cdot\dfrac{12}{7}=\dfrac{-63}{28}=-\dfrac{9}{4}\)

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

hay \(x=\dfrac{1}{4}:\dfrac{1}{6}=\dfrac{3}{2}\)

e: \(\Leftrightarrow\dfrac{1}{2}:x=-4-\dfrac{1}{3}=-\dfrac{17}{3}\)

hay \(x=-\dfrac{1}{2}:\dfrac{17}{3}=\dfrac{-3}{34}\)

dad

\(11\left(x-6\right)=4x+11\Leftrightarrow11x-4x=11+66\Leftrightarrow7x=77\Leftrightarrow x=11\)

11(x-6)=4x+11

=>11x-4x=11+66

=>7x=77

=>x=77:7

=>x=11

vậy x=11

\(11\times\left(x-6\right)=4\times x+11\)

\(\Rightarrow11\times x-66=4\times x+11\)

\(\Rightarrow11\times x-4\times x=66+11\)

\(\Rightarrow77\times x=77\)

\(\Rightarrow x=1\)

b) \(\left(2\times x-10\right)\times\left(25-25\times x\right)=0\)

\(\Rightarrow\orbr{\begin{cases}2\times x-10=0\\25-25\times x=0\end{cases}\Rightarrow\orbr{\begin{cases}x=5\\x=1\end{cases}}}\)

a)11x(X-6)=4xX+11

   11xX-11x6=4xX+11

    11xX-4xX=11x6+11

    (11-4)xX=66+11

      7xX=77

       x=77:7

       x=11

b)(2xX-10)x(25-25xX)=0

=>2xX-10=0=>2xX=10 =>x=10:2=5

hoặc 25-25xX=0=>25xX=25=>x=25:25=1

Vậy x=1 hoặc x=5

Tích ch0 mình nha

Cảm ơn bạn nhìu

a)11x(X-6)=4xX+11

   11xX-11x6=4xX+11

    11xX-4xX=11x6+11

    (11-4)xX=66+11

      7xX=77

       x=77:7

       x=11

b)(2xX-10)x(25-25xX)=0

=>2xX-10=0=>2xX=10 =>x=10:2=5

hoặc 25-25xX=0=>25xX=25=>x=25:25=1

Vậy x=1 hoặc x=5

a)11(x-6) = 4x +11

<=> 11x-66 =4x+11

<=>11x-4x =11+66

<=>7x = 77

<=> x =11

b) \(|x-3|+1=x\)

 \(\Leftrightarrow|x-3|=x-1\)

\(\Leftrightarrow\)\(\orbr{\begin{cases}x-3=x-1\\x-3=-x+1\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}0x=2\\2x=4\end{cases}}\)

\(\Leftrightarrow x=2\)

c) (4x - 8)[x + (-3)] = 0

=> 4(x - 2)(x - 3) = 0

=> (x - 2)(x - 3) = 0

=> x - 2 = 0 hoặc x - 3 = 0

+) x - 2 = 0 => x = 2

+) x - 3 = 0 => x = 3

Vậy x \(\in\){2;3}

11(x - 6) = 4x + 11

=> 11x - 66 = 4x + 11

=> 11x - 4x = 11 + 66

=> 7x = 77

=> x = 77/7

=> x = 11

11(6-x)-4x=11

=>66-11x-4x=11

=>66-15x=11

=>15x=66-11=55

=>\(x=\dfrac{55}{15}=\dfrac{11}{3}\)

Bài 1 : 

\(=\dfrac{2}{11}+\dfrac{4}{11}-\dfrac{6}{11}-\dfrac{3}{8}-\dfrac{5}{8}=0-1=-1\)

Bài 2 : 

\(\Rightarrow3+x=8\Leftrightarrow x=5\)

Bài 3 : 

\(\Leftrightarrow x-\dfrac{5}{11}=\dfrac{5}{4}\Leftrightarrow x=\dfrac{35}{44}\)

Bài 4 : 

Trong 2 ngày An đọc được số quyên phần quyên sách 

\(\dfrac{1}{11}+\dfrac{8}{11}=\dfrac{9}{11}\)( quyển sách ) 

đs : 9/11 quyển sách 

\(-4+x=-4+7\)

\(\Rightarrow x=-4+7+4\)

\(\Rightarrow x=7\)

\(\left(-3\right)-\left(-5-x\right)=-15+\left(-6+15\right)\)

\(\Rightarrow x=-15-6+15+3-5\)

\(\Rightarrow x=-8\)

\(-\left(x+2\right)+2=\left(8-15\right)+15\)

\(\Rightarrow-x+2+2=-7+15\)

\(\Rightarrow-x=-7+15-2-2\)

\(\Rightarrow x=-4\)

\(4+\left(x-4\right)=-\left(11-2\right)+\left(11+4\right)\)

\(\Rightarrow4+x-4=-11+2+11+4\)

\(\Rightarrow x=-11+2+11+4-4+4\)

\(\Rightarrow x=6\)

a) -4 + x = -4 + 7            b) (-3) - (-5-x) = -15 + (-6+15)

   -4 + x + 4 - 7 = 0            (-3) + 5 + x = -6

        x - 7 = 0                     2 + 6 = -x

        x= 7                            8 = -x 

 Vậy x= 7                            x= -8   =) Vậy x= -8

c) -(x+2)+2=(8-15)+15          d) 4+(x-4)= -(11-2) + (11+4 )

   -x - 2 + 2 = 8                       4+x-4 = 6

   -x = 8                                     x=6

    x= -8                              Vậy x=6

Vậy x= -8