a: =>x+61=74

hay x=13

b: =>x-35=120

hay x=155

d: =>7x=721

hay x=103

a) 124 + (118 - x) = 217

118 - x = 217 - 124

118 - x = 93

x = 118 - 93

x = 25

b) 156 - (x + 61) = 82

x + 61 = 156 - 82

x + 61 = 74

x = 74 - 61

x = 13

c) 219 - 7(x + 1) = 100

7(x + 1) = 219 - 100

7(x + 1) = 119

x + 1 = 119 : 7

x + 1 = 17

x = 17 - 1

x = 16

d) (3x - 6).3 = 3⁴

3x - 6 = 3⁴ : 3

3x - 6 = 3³

3x - 6 = 27

3x = 27 + 6

3x = 33

x = 33 : 3

x = 11

e) 231 - (x - 6) = 1339 : 13

231 - (x - 6) = 103

x - 6 = 231 - 103

x - 6 = 128

x = 128 + 6

x = 134

a) 124 + (118 - x) = 217

118 - x = 217 - 124

118 - x = 93

x = 118 - 93

x = 25

b) 156 - (x + 61) = 82

x + 61 = 156 - 82

x + 61 = 74

x = 74 - 61

x = 13

c) 219 - 7(x + 1) = 100

7(x + 1) = 219 - 100

7(x + 1) = 119

x + 1 = 119 : 7

x + 1 = 17

x = 17 - 1

x = 16

d) (3x - 6) . 3 = 3⁴

(3x - 6) . 3 = 81

(3x - 6) = 81 : 3

(3x - 6) = 27

3x = 27 + 6

3x = 33

x = 33 : 3 

x = 11

e) 231 - (x - 6) = 1339 : 13

231 - (x - 6) = 103

(x - 6) = 231 - 103

x - 6 = 128

x = 128 + 6

x = 134

cô cấm dùng máy tính -) 

lớp 9 ms đc dùng:_)

a) 124 + (118 - x) = 217

     242           - x  = 217

                        x  = 242 - 217

                        x  = 25

câu b nữa

(x-36)/18=12

=>x-36=12*18

=>x-36=216

=>x=216+36

=>x=252

a)(x-35)-120=0                            b)124+(118-x)=217                             c)156-(x+61)=82

x-35          = 0+120=120                118-x         =217-124=93                     x+61        = 156-82=74

x              = 120+35=155               x               = 118-93=25                     x              =74-61=13

suy ra x=155                                suy ra x= 25                                       suy ra x=13

a) ( x - 35 ) - 120 = 0

<=> x - 35 = 120

<=> x = 155

b) 124 + ( 118 - x ) = 217

<=> 118 - x = 93

<=> x = 25

c) 156 - ( x + 61 ) = 82

<=> x + 61 = 74

<=> x = 13

a, (x - 35) - 120 = 0

=> x - 35 = 120

=> x = 155

b, 124 + (118 - x) = 217

=> 118 - x = 93

=> x = 25

c, 156 - (x + 61) = 82

=> x + 61 = 74

=> x = 13

a) x = 155

b) x = 25

c) x = 13

2x - 35 = 15

      2x = 15 + 35 

      2x = 50

        x = 50 : 2

        x = 25 

( x - 1 ) + 5 = 17

          x - 1 = 17 - 5 

          x - 1 = 12

               x = 12 + 1

               x = 13 

124 + (118 – x ) = 217

118 – x = 217 – 124

118 – x = 93

x = 118 – 93

x = 25.

a, ( x - 35 ) - 120 = 0

( x - 35 ) = 0 + 120

x - 35 = 120

x = 120 + 35

x = 155

Vậy x = 155

b, 124 + ( 118 - x ) = 217

( 118 - x ) = 217 - 124

118 - x = 93

x = 118 - 93

x = 25

Vậy x = 25

c, 156 - ( x + 61 ) = 82

( x + 61 ) = 156 - 82

x + 61 = 74

x = 74 - 61

x = 13 

Vậy x = 13

a) \(\left(x-35\right)-120=0\)

\(\Rightarrow x-35=0+120\)

\(\Rightarrow x=120+35\)

\(\Rightarrow x=155\)

b) \(124+\left(118-x\right)=217\)

\(\Rightarrow118-x=217-124\)

\(\Rightarrow x=118-93\)

\(\Rightarrow x=25\)

c) \(156-\left(x+61\right)=82\)

\(\Rightarrow x+61=156-82\)

\(\Rightarrow x=74-61\)

\(\Rightarrow x=13\)

a) \(x=155\)

b) \(x=25\)

c) \(x=13\)

(Nhớ k cho mình với nhoa!)

a) ( x - 35 ) - 120 = 0

<=> x - 35 = 120

<=> x = 155

b) 124 + ( 118 - x ) = 217

<=> 118 - x = 93

<=> x = 25

c) 156 - ( x + 61 ) = 82

<=> x + 61 = 74

<=> x = 13