`#3107.101107`

a,

`2x + 3x = 5^7 \div 5^5`

$\Rightarrow (2 + 3)x = 5^{7 - 5}$

$\Rightarrow 5x = 5^2$

$\Rightarrow 5x = 25$

$\Rightarrow x = 25 \div 5$

$\Rightarrow x = 5$

Vậy, `x = 5`

b,

`5(7x - 45) = 2^3 . 5^2 - 3^2 . 20`

`\Rightarrow 5(7x - 45) = 8.25 - 9.20`

`\Rightarrow 5(7x - 45) = 40.5 - 36.5`

`\Rightarrow 5(7x - 45) = 5.(40 - 36)`

`\Rightarrow 5(7x - 45) = 5.4`

`\Rightarrow 7x - 45 = 4`

`\Rightarrow 7x = 49`

`\Rightarrow x = 49 \div 7`

`\Rightarrow x = 7`

Vậy, `x = 7.`

A) (2+3).x=5 mũ 2

 5.x=5 mũ 2

5.x=25

x=25:5

x=5 

vậy x=5 

câu B ko bt làm bn ạ

giải i mn huhu pls

cần dc giải mai tui họccc

\(60+x-34=43\Rightarrow x=43+34-60=17\)

\(23x-6.23+69x=230\)

\(\Rightarrow23x+69x=230+6.23\)

\(\Rightarrow92x=368\Rightarrow x=368:92\Rightarrow x=4\)

\(\left(15.24-x\right):0,25=100:0,25\)

\(\Rightarrow\left(360-x\right)=100:0,25.0,25\)

\(\Rightarrow360-x=100\Rightarrow x=360-100=260\)

\(\left(7x+8\right):5=10\Rightarrow\left(7x+8\right)=10.5\)

\(\Rightarrow7x+8=50\Rightarrow7x=50-8\Rightarrow7x=42\Rightarrow x=42:7=6\)

\(280:\left(7+3x\right)=4\Rightarrow\left(7+3x\right)=280:4\)

\(\Rightarrow7+3x=70\Rightarrow3x=70-7\Rightarrow3x=63\Rightarrow x=63:3=21\)

\(\left(x+5\right)x19:13=57\)

\(\Rightarrow\left(x+5\right)x19=57.13\)

\(\Rightarrow\left(x+5\right)=741:19\Rightarrow x+5=39\Rightarrow x=39-5=34\)

\(4\left(36-4x\right)=64\)

\(\Rightarrow\left(36-4x\right)=64:4\)

\(\Rightarrow36-4x=16\)

\(\Rightarrow4x=36-16\Rightarrow4x=20\Rightarrow x=20:4=5\)

\(\left(7,6:1,9\right)x=3,2\)

\(\Rightarrow4x=3,2\Rightarrow x=3,2:4=0,8\)

\(\left(x:2+50\right):5=12\)

\(\Rightarrow x:2+50=12.5\)

\(\Rightarrow x:2=60-50\Rightarrow x:2=10\Rightarrow x=10.2=20\)

cứu tui

a, 5(x – 7) = 0

x – 7 = 0

x = 7

b, 95 – 5(x+2) = 45

5(x+2) = 40

x+2 = 8

x = 6

c,  6 2 x + 2 3 + 40 = 100

6(2x+8) = 60

2x+8 = 10

x = 1

d, 3(3x+9)+6 = 96

3(3x+9) = 90

3x+9 = 30

3x = 27

x = 9

e,  2 6 + 5 + x = 3 4

5+x = 81–64

5+x = 17

x = 12

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: Sai

b: S

c: Đ

d: S

a,S

b,S

c,Đ

d,S

a) S

b) S

c) Đ

d) S

Đặt \(t=\sqrt{x^2+4\sqrt{5}}\to t>0.\)  Phương trình trở thành \(\frac{\left(2t^2-7\right)^2-161}{4}=\left(34-3t^2\right)t\Leftrightarrow\left(2t^2-7\right)^2-161=4t\left(34-3t^2\right)\)
\(\Leftrightarrow\left(t^2-2t-4\right)\left(t^2+5t+7\right)=0\Leftrightarrow t^2-2t=4\Leftrightarrow t=1+\sqrt{5}.\)  (Vì t>0)

Vậy ta được \(x^2+4\sqrt{5}=\left(1+\sqrt{5}\right)^2\Leftrightarrow x^2=\left(\sqrt{5}-1\right)^2\Leftrightarrow x=\pm\left(\sqrt{5}-1\right).\)

 

a) (x - 7) + 5 = 16

=>   x - 7 = 11

=>  x  =  18

b) 4 : x - 34 = 6

=>  4 : x = 40

=>  x  =  \(\frac{1}{10}\)

c) 120 : ( x - 1 ) + 3 = 23

=>  120 : ( x - 1 ) = 20

=>  x - 1 = 6

=>  x  = 7

d) 170 - ( x-7) : 5 = 20

=>  ( x - 7 ) : 5 = 150

=>  x - 7  = 750

=>   x   =  757

e) x + 12 + 2 .x + 3 = 4.x + 3

=>  3x + 17  = 4x  + 3

=>  x  = 15 

\(a,x-7=11\)

\(x=18\)

\(b,x-36=\frac{2}{3}\)

\(x=\frac{110}{3}\)

\(c,120:\left(x-1\right)=20\)

\(x-1=6\)

\(x=7\)

\(d,\left(x-7\right):5=150\)

\(x-7=10\)

\(x=17\)

\(d,x+12+2.x+3-4.x-3=0\)

\(x.\left(1+2-4\right)+3-3+12=0\)

\(x.\left(-1\right)+12=0\)

\(x.\left(-1\right)=-12\)

\(x=12\)

a) (x - 7) + 5 = 16

x - 7 = 16 - 5 

x - 7 = 11

x = 11 + 7

x = 18

b) 4 : x - 34 = 6

4 : x = 6 + 34

4 : x = 40

x = 4 : 40

x = 1/10

c) 120 : ( x - 1 ) + 3 =23

120 : ( x - 1 ) = 23 +3

120 : ( x - 1 ) =26

x -1 = 120 :26

x - 1 =13/60

x = 13/60 + 1

x = 73/60

d) 170 - ( x - 7 ) :5 =20

170 - ( x - 7 ) = 20:5

170 - ( x - 7 ) =4

x- 7 = 170 - 4

x - 7 = 166

x = 166 + 7

x = 173

còn câu e mik ko bt làm nhé mà k cho mik nhé