\(a,x-\dfrac{1}{4}=\dfrac{7}{2}.\dfrac{-3}{5}\\ \Rightarrow x-\dfrac{1}{4}=\dfrac{-21}{10}\\ \Rightarrow x=\dfrac{-21}{10}+\dfrac{1}{4}\\ \Rightarrow x=\dfrac{-37}{20}\\ b,\dfrac{x}{134}=\dfrac{9}{7}.\dfrac{5}{-11}\\ \Rightarrow\dfrac{x}{134}=\dfrac{-45}{77}\\ \Rightarrow x=\dfrac{-45}{77}.134\\ \Rightarrow x=\dfrac{-6030}{77}\)

\(x-\dfrac{1}{4}=\dfrac{7}{2}\cdot\dfrac{-3}{5}\)

\(x-\dfrac{1}{4}=\dfrac{-21}{10}\)

\(x=\dfrac{-21}{10}+\dfrac{1}{4}\)

\(x=\dfrac{-37}{20}\)

b ) \(\dfrac{x}{134}=\dfrac{9}{7}\cdot\dfrac{5}{-11}\)

      \(\dfrac{x}{134}=\dfrac{9}{7}\cdot\dfrac{-5}{11}\)

       \(\dfrac{x}{134}=\dfrac{-45}{77}\)

       \(x=\dfrac{-45}{77}\cdot134\)

       \(x=-\dfrac{6034}{77}\)

a: =>7(135:x-13)=14

=>135:x-13=2

=>135:x=15

=>x=9

b: =>11x-66-4x=11

=>7x=77

=>x=11

\(120+\left(135:x-13\right)\cdot7=134\)

\(\Rightarrow\left(135:x-13\right)\cdot7=134-120\)

\(\Rightarrow\left(135:x-13\right)\cdot7=14\)

\(\Rightarrow135:x-13=14:7\)

\(\Rightarrow135:x=2+13\)

\(\Rightarrow135:x=15\)

\(\Rightarrow x=135:15\)

\(\Rightarrow x=9\)

_______________

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

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

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

\(\Rightarrow7\cdot x=77\)

\(\Rightarrow x=77:7\)

\(\Rightarrow x=11\)

\(a,120+\left(135\div x-13\right)\times7=134\)

\(\Rightarrow\left(135\div x-13\right)\times7=14\)

\(\Rightarrow135\div x-13=2\)

\(\Rightarrow135\div x=15\)

\(\Rightarrow x=135\div15=9\)

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

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

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

\(\Rightarrow\left(11-4\right)\times x=77\)

\(\Rightarrow7\times x=77\Leftrightarrow x=11\)

x = -15

134-4.(11-x)=30

=>4.(11-x)=134-30

=>4.(11-x)=104

=>11-x=104:4

=>11-x=26

=>x=11-26

=>x= -15

134-4.(11-x)=30

⇒4.(11-x)=134-30

⇒4.(11-x)=104

⇒11-x=104:4

⇒11-x=26

⇒x=11-26

⇒x= -14

Vậy x= -14

đúng thì cho tik nha

a) (x + 23) - 14 = 11

=> x + 23 - 14 = 11

=> x + 9 = 11

=> x = 11 - 9 = 2

b) 2.x + 13 = 43

=> 2.x = 43 - 13

=> 2.x = 30

=> x = 15

c) 2(x - 1) - 156 = 196

=> 2x - 2 = 352

=> 2x = 354

=> x = 177

3(134 - x) + 1 = 211

=> 3(134 - x) = 210

=> 134 - x = 70

=> x = 134 - 70 = 64

h) 156 - 2(x + 2) = 128

=> 2(x + 2) = 156 - 128 = 28

=> x + 2 = 28 : 2

=> x + 2 = 14

=> x = 12

`136 -4^2 : x=134`

`=> 136-16:x=134`

`=> 16:x= 136-134`

`=> 16:x=2`

`=>x=16:2`

`=>x=8`

__

`19-5(x-1)=4`

`=> 5(x-1)=19-4`

`=> 5(x-1) =15`

`=> x-1=15:5`

`=>x-1=3`

`=>x=3+1`

`=>x=4`

__

`257-(x^2-1) =177`

`=>x^2-1=257-177`

`=>x^2-1=80`

`=>x^2=80+1`

`=>x^2=81`

`=>x^2=(+- 9)^2`

`=> x= +- 9`

__

`(x^2-17) : 8=2^3`

`=> x^2 -17 = 8 * 8`

`=> x^2 -17= 64`

`=> x^2 =64+17`

`=>x^2=81`

`=>x^2=(+- 9)^2`

`=> x= +- 9`

136 - 4² : x = 134

4² : x = 136 - 134

8 : x = 2

x = 8 : 2

x = 4

--------

129 - 5(x - 1) = 4

5(x - 1) = 129 - 4

5(x - 1) = 125

x - 1 = 125 : 5

x - 1 = 25

x = 25 + 1

x = 26

------------

257 - (x² - 1) = 177

x² - 1 = 257 - 177

x² - 1 = 80

x² = 80 + 1

x² = 81

x = -9 hoặc x = 9

--------

(x² - 17) : 8 = 8

x² - 17 = 8 . 8

x² - 17 = 64

x² = 64 + 17

x² = 81

x = -9 hoặc x = 9

a,\(\left(x-15\right):50+22=24\)

\(< =>\frac{\left(x-15\right)}{50}=2< =>x-15=100\)

\(< =>x=100+15=115\)

b,\(42-\left(2x+32\right)+12:2=6\)

\(< =>42-2x-32=0\)

\(< =>10-2x=0< =>x=\frac{10}{2}=5\)

Làm nốt :

c) \(134-2\left\{156-6\cdot\left[54-2\cdot\left(9+6\right)\right]\right\}\cdot x=86\)

=> 134 - 2{156 - 6 . [54 - 2 . 15]} . x = 86

=> 134 - 2{156 - 6 . [54 - 30]} . x = 86

=> 134 - 2{156 - 6. 24} . x = 86

=> 134 - 2{156 - 144} . x = 86

=> 134 - 2.12 . x = 86

=> 134 - 24 . x = 86

=> 24.x = 48

=> x = 2

Bài 2 : a) 120 : [21 - (4x - 4)] = 2³.3

=> 120 : [21 - (4x - 4)] = 8.3

=> 120 : [21 - (4x - 4)] = 24

=> 21 - (4x - 4) = 5

=> 4x - 4 = 16

=> 4x = 20

=> x = 5

b) 3.[205 - (x - 9)] - 486 = 0

=> 3.[205 - (x - 9)] = 486

=> 205 - (x - 9) = 162

=> x - 9 = 205 - 162 = 43

=> x = 43 + 9 = 52

c) 204 - 2{200 - 5.[64 - 2.(11 + 6)]} . x = 4

=> 204 - 2{200 - 5.[64 - 2.17]} . x = 4

=> 204 - 2{200 - 5 .[64 - 34]}.x = 4

=> 204 - 2{200 - 5.30} . x = 4

=> 204 - 2{200 - 150}.x = 4

=> 204 - 2.50 . x = 4

=> 2.50.x = 200

=> 100.x = 200

=> x = 2

a) (−11)² − 15(x − 2) = 134 − 16x

121 - 15x + 30 = 134 - 16x

16x - 15x = 134 - 121 - 30

x = -17

b) (4x + 1)(x² − 16)=0

(4x + 1)(x - 4)(x + 4) = 0

\(\left[\begin{matrix}4x+1=0\\x-4=0\\x+4=0\end{matrix}\right.\)

\(\left[\begin{matrix}4x=-1\\x=4\\x=-4\end{matrix}\right.\)

\(\left[\begin{matrix}x=-\frac{1}{4}\\x=4\\x=-4\end{matrix}\right.\)

c) − 2(x − 3) + (− 2)² = 4 − 3x

3x + 4 - 2x + 6 = 4

x = 4 - 4 - 6

x = - 6

Nguyễn Huy TúPhương An