x+1000-200=2000

x+1000=2200

x=2200-1000

x=1200

70-5.(x-3)=45

5.(x-3)=70-45

5.(x-3)=25

x-3=5

x=8

x+1 000 - 200 = 2 000 

x + 1000=2200

x=1200

vậy x=1200.

70-5.(x-3)=45

5.(x-3)=25

x-3=5

x=8.

vậy x=8.

x + 1000 - 200 = 2000

x + 1000 = 2000 + 200

x + 1000 = 2200

          x = 2200 - 1000

          x = 1200

70 - 5.(x - 3) = 45

       5.(x - 3) = 70 - 45

       5.(x - 3) = 25

           x - 3 = 25 : 5 

           x - 3 = 5

                x = 5 + 3

                x = 8

a) \(70-\left(x-3\right)=45\)

\(x-3=70-45\)

\(x-3=25\)

\(x=25+3\)

\(x=28\)

b) \(12+\left(5+x\right)=20\)

\(5+x=20-12\)

\(5+x=8\)

\(x=8-5\)

\(x=3\)

c) \(130-\left(100+x\right)=25\)

\(100+x=130-25\)

\(100+x=105\)

\(x=105-100\)

\(x=5\)

d) \(175+\left(30-x\right)=200\)

\(30-x=200-175\)

\(30-x=25\)

\(x=30-25\)

\(x=5\)

e) \(\left(x+12\right)+22=92\)

\(x+12=92-22\)

\(x+12=70\)

\(x=70-12\)

\(x=58\)

f) \(95-\left(x+2\right)=45\)

\(x+2=95-45\)

\(x+2=50\)

\(x=50-2\)

\(x=48\)

a)

70 - (x - 3) = 45

x - 3 = 70 - 45 = 25

x = 25 + 3 = 28

Vậy x = 28

b)

12 + (5 + x) = 20

5 + x = 20 - 12 = 8

x = 8 - 5 = 3

Vậy x = 3

c)

130 - (100 + x) = 25

100 + x = 130 - 25 = 115

x = 115 - 100 = 15

Vậy x = 15

d)

175 + (30 - x) = 200

30 - x = 200 - 175 = 25

x = 30 - 25 = 5

Vậy x = 5

e)

(x + 12) + 22 = 92

x + 12 = 92 - 22 = 70

x = 70 - 12 = 58

Vậy x = 58

f)

95 - (x + 2) = 45

x + 2 = 95 - 45 = 50

x = 50 - 2 = 48

Vậy x = 48

câu c sai r kìa bạn

a) \(70-5\left(x-3\right)=45\)

\(5\left(x-3\right)=25\)

\(x-3=5\)

\(\Rightarrow x=8\)

b) \(12+\left(5+x\right)=20\)

\(5+x=8\)

\(\Rightarrow x=3\)

c) \(130-\left(100+x\right)=25\)

\(100+x=105\)

\(\Rightarrow x=5\)

d) \(175+\left(30-x\right)=200\)

\(30-x=25\)

\(\Rightarrow x=5\)

e) \(5\left(x+12\right)+22=92\)

\(5\left(x+12\right)=70\)

\(x+12=14\)

\(\Rightarrow x=2\)

a. 70 - 5.(x - 3) = 45

5.(x - 3)             = 70 - 45

x - 3                  = 25 : 5

x                       = 5 + 3

x                       = 8

b. 12 + (5 + x) = 20

5 + x               = 20 - 12

x                     = 8 - 5

x                     = 3

c. 130 - (100 + x) = 25

100 + x                = 130 - 25

x                          = 105 - 100

x                         = 5

d. 175 + (30 - x) = 200

30 - x                 = 200 - 175

x                        = 30 - 25

x                        = 5

e. 5.(x + 12) + 22 = 92

5.(x + 12)             = 92 - 22

x + 12                  = 70 : 5

x                          = 14 - 12

x                          = 2

admin là con chó

b giúp mk câu hỏi của mkn nha

Sai đó bn 

mk tính rồi 277 x 277 = 76729

200 x 200 + 70 x 70 + 7 x 7 = 44949

tk nk nhé

Sai.Vì:277*277=76729 mà 200*200+70*70+7*7=44949

Bmin =100

Cmin=90

Dmin =120

1) 70 - 5( x - 3 ) = 45

5( x - 3 ) = 70 - 45

5( x - 3 ) = 25

x - 3 = 25 : 5

x - 3 = 5

x = 5 + 3

x = 8

2) 12 + ( 5 + x ) = 20

5 + x = 20 - 12

5 + x = 8

x = 8 - 5

x = 3

3) 130 - ( 100 + x ) = 25

100 + x = 130 - 25

100 + x = 105

x = 105 - 100

x = 5

4) 175 + ( 30 - x ) = 200

30 - x = 200 - 175

30 - x = 25

x = 30 - 25

x = 5

5) 5( x + 12 ) + 22 = 92

5( x + 12 ) = 92 - 22

5( x + 12 ) = 70

x + 12 = 70 : 5

x + 12 = 14

x = 14 - 12

x = 2

6) 95 - 5( x + 2 ) = 45

5( x + 2 ) = 95 - 45

5( x + 2 ) = 50

x + 2 = 50 : 5

x + 2 = 10

x = 10 - 2

x = 8

7) 14x + 54 = 82

14x = 82 - 54

14x = 28

x = 28 : 14

x = 2

8) 15x - 133 = 17

15x = 17 + 133

15x = 150

x = 150 : 15

x = 10

9) 155 - 10( x + 1 ) = 55

10( x + 1 ) = 155 - 55

10( x + 1 ) = 100

x + 1 = 100 : 10

x + 1 = 10

x = 10 - 1

x = 9

1)

a) 2x + 5 = 3⁴ : 3²

2x + 5 = 3²

2x + 5 = 9

2x = 9 - 5

2x = 4

x = 4 : 2

x = 2

b) (3x - 24).73 = 2.74

(3x - 24).73 = 148

3x - 24 = 148/73

3x = 148/73 + 24

3x = 1900/73

x = 1900/73 : 3

x = 1900/219

c) [3.(42 - x)] + 15 = 23.3

126 - 3x + 15 = 69

141 - 3x = 69

3x = 141 - 69

3x = 72

x = 72 : 3

x = 24

d) 126 + (132 - x) = 300

132 - x = 300 - 126

132 - x = 174

x = 132 - 174

x = -42

2)

a) 120 - (x + 55) = 60

x + 55 = 120 - 60

x + 155 = 60

x = 60 - 55

x = 5

b) (7x - 11).3 = 25.52 + 200

(7x - 11).3 = 1500

7x - 11 = 1500 : 3

7x - 11 = 500

7x = 500 + 11

7x = 511

x = 511 : 7

x = 73

c) 2x + 2x + 4 = 544

4x = 544 - 4

4x = 540

x = 540 : 4

x = 135

3) 

a) 10 + 2x = 49 : 47

10 + 2x = 49/47

2x = 49/47 - 10

2x = -421/47

x = -421/47 : 2

x = -421/94

b) 70 - 5(x - 3) = 45

5(x - 3) = 70 - 45

5(x - 3) = 25

x - 3 = 25 : 5

x - 3 = 5

x = 5 + 3

x = 8

c) 4 + 95 : x = 143 : 142 - 23

4 + 95 : x = -3123/142

95 : x = -3123/142 - 4

95 : x = -3691/142

x = 95 : (-3691/142)

x = -13490/3691