\(\Leftrightarrow2x=74\)

hay x=37

2x-49=45

2x=45+49

2x=94

x=94:2

x=47

7) -4(x +41) = 400

x + 41 = 400 : -4 = -100

x = -100 - 41 = 141

8) 2x - 49 = 5 . 3² = 5 . 9

2x =  9 + 49 = 58

x = 58 : 2 = 29

7) \(-4x-246=400\Leftrightarrow-4x=646\Leftrightarrow x=-161,5\)

8) \(2x-49=45\Leftrightarrow2x=94\Leftrightarrow x=47\)

d)5( x+4)=135-35

       x+4=100:5

       x    =20-4

      x     =16

d) 135 - 5 (x+4) = 35

5 (x+4) = 135 - 35

5 (x+4) = 100

(x+4) = 100 : 5

x + 4 = 20

x = 20 - 4

x = 16

e) 25 + 3 ( x - 8 ) = 106 

3  ( x - 8 ) = 106 - 25 

3  ( x - 8 ) = 81 

x - 8 = 81 : 3 

x - 8 = 27 

x = 27 + 8 

x = 35 

f) 2x – 49 = 5. 32

2x - 49 = 160

2x = 160 + 49

2x = 209

x = 209 : 2

x = 104,5

d)\(135-5\left(x+4\right)=35\)

⇔\(5\left(x+4\right)=100\)

⇔\(x+4=20\)

⇔\(x=16\)

e)\(25+3\left(x-8\right)=106\)

⇔\(3\left(x-8\right)=81\)

⇔\(x-8=27\)

⇔\(x=35\)

f)\(2x-49=5.32\)

⇔\(2x-49=160\)

⇔\(2x=209\)

⇔\(x=\dfrac{209}{2}\)

6: \(\Leftrightarrow x-8=20\)

hay x=28

\(\left(x+1\right)^3=2^3.3+3\)

\(\Rightarrow\left(x+1\right)^3=24+3=27=3^3\)

\(\Rightarrow x+1=3\Rightarrow x=2\)

\(5+2.3^x+2=23\)

\(\Rightarrow7+2.3^x=23\)

\(\Rightarrow2.3^x=23-7=16\)

\(\Rightarrow3^x=8.\)

Mà số 3 lũy thừa mấy cũng không thể bằng 8 => x không thỏa mãn.

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

a/ x + 2x + 3x = 36

=> 6x = 36

=> x = 6

Vậy ..

b/ 7x - 2x - x = 24

=> 4x = 24

=> x = 6

Vậy ...

c/ (x : 5) - 10 = 5

=> x : 5 = 15

=> x = 75

Vậy ...

d/ 7. (x+3) = 49

=> x + 3 = 7

=> x = 4

Vậy ....

e/ (x - 5) . 4 = 32

=> x - 5 = 8

=> x = 13

Vậy. ..

g/ 7x - 3 = 25

=> 7x = 28

=> x = 4

Vậy ...

h/ 17 - (x :3) = 10

=> x : 3 = 17 - 10

=>x : 3 = 7

=> x = 21

Vậy ..

a) x + 2x + 3x = 36 

=> 6x = 36

=> x = 6

b)7x - 2x - x = 24

=> 4x = 24 

=> x = 6

c) (x : 5 ) - 10 = 5

=> x : 5 = 15

=> x = 3

d) 7 . ( x + 3 ) = 49

=> x + 3 = 7

=> x = 4

e) ( x - 5 ) .  4 =32 

=> x - 5 = 8

=> x = 3

g) 7x - 3 = 25 

=> 7x = 28

=> x = 4

h) 17 - ( x : 3 ) = 10

=> x : 3 = 7

=> x = 21

a) x + 2x + 3x = 36

=> 6x = 36 =>  x = 36 : 6 = 6.

b) 7x - 2x -x = 24

=> 4x = 24 => x = 24 : 4 = 6.

c)(x : 5) - 10 = 5

=> x : 5 = 5 + 10 = 15

=> x  = 15 x 5 = 75.

d) 7. (x + 3) = 49

=> x + 3 = 49 : 7 = 7

=> x = 7 - 3 = 4.

e)(x - 5) . 4 = 32

=> x - 5 = 32 : 4 = 8

=> x = 8 + 5 = 13.

g) 7x - 3 = 25

=> 7x = 25 + 3 = 28 => x = 28 : 7 = 4

h) 17 - ( x : 3 ) = 10

=> x : 3 = 17 - 10 = 7

=> x = 7.3 = 21

\(=49+\dfrac{8}{23}-5-\dfrac{7}{32}-14-\dfrac{8}{32}\)

\(=30-\dfrac{89}{736}=\dfrac{21991}{736}\)

=30−89/736=21991/736

= 21991/736

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Đơn giản mà bạn

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