K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

18 tháng 11 2016

a ) 2x + 5 = 17

     2x = 17 - 5

     2x = 12

       x = 12 : 2 

       x = 6

b ) -14 + 3x = 13

             3x = 13 - ( -14 )

             3x =  -27

              x =  -27 : 3

              x = -9

c ) 4x - 13 = -77

     4x = ( -77 ) + 13

     4x = 64

       x = 64 : 4

       x = 16

     

18 tháng 11 2016

\(a,2x+5=17\)

            \(2x=17-5\)

            \(2x=12\)

               \(x=12:2\)

               \(x=6\)

\(b,-14+3x=13\)

                     \(3x=13+14\)

                     \(3x=27\)

                        \(x=27:3\)

                        \(x=9\)

\(c,4x-13=-77\)

               \(4x=-77+13\)

               \(4x=-64\)

                  \(x=-64:4\)

                  \(x=-16\)

18 tháng 9 2023

2x - 3 = 17

2x = 17 + 3

2x = 20

x = 20 : 2

x = 10

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

4² - 3x = 27.3 - 77

16 - 3x = 81 - 77

16 - 3x = 4

3x = 16 - 4

3x = 12

x = 12 : 3

x = 4

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

48 + 2x = 3.2³

48 + 2x = 3.8

48 + 2x = 24

2x = 24 - 48

2x = -24

x = -24 : 2

x = -12

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

(13x - 12²) : 5 = 5

13x - 144 = 5.5

13x - 144 = 25

13x = 25 + 144

13x = 169

x = 169 : 13

x = 13

18 tháng 9 2023

\(2x-3=17\)

\(2x=17+3\)

\(2x=20\)

\(x=20:2\)

\(x=10\)

____

\(4^2-3x=27.3-77\)

\(16-3x=81-77\)

\(16-3x=4\)

\(3x=16-4\)

\(3x=12\)

\(x=12:3\)

\(x=4\)

_____

\(48+2x=3.2^3\)

\(48+2x=3.8=24\)

\(2x=24-48\)

\(2x=\left(-24\right)\)

\(x=\left(-24\right):2\)

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

____

\(\left(13x-12^2\right):5=5\)

\(\left(13x-144\right):5=5\)

\(13x-144=5.5\)

\(13x-144=25\)

\(13x=25+144\)

\(13x=169\)

\(x=169:13\)

\(x=13\)

6 tháng 3 2018

1. 3y = 0

=> y = 0

2. 1+x = 0

<+ x = -1

3.

\(1-2t=0\)

\(\Leftrightarrow2t=1\)

\(\Leftrightarrow\dfrac{1}{2}\)

4. 2x +x + 3 =0

\(\Leftrightarrow3x+3=0\)

\(\Leftrightarrow x=-3\)

5.

\(25x-20=0\)

\(\Leftrightarrow25x=20\)

\(\Leftrightarrow x=\dfrac{4}{5}\)

6 tháng 3 2018

7.

2x-3 = x+5

<=> 2x - x = 5+3

<=> x = 8

8.

x-8=2x+3

<=> x - 2x = 3+8

<=> -x = 11

<=> x = -11

9. 17-2x = 3x-5

<=> -2x-3x = -5-17

<=> -5x = -22

<=> x = \(\dfrac{22}{5}\)

10.

2x+x+22=0

<=> 3x+22=0

<=> 3x = -22

<=> x = \(\dfrac{-22}{3}\)

Mấy bài kia tự giải tương tự nhá!!!

2 tháng 6 2017

a) \(\dfrac{2}{3}x-\dfrac{1}{2}=\dfrac{1}{10}\)

\(\dfrac{2}{3}x=\dfrac{1}{10}+\dfrac{1}{2}=\dfrac{3}{5}\)

\(x=\dfrac{3}{5}:\dfrac{2}{3}=\dfrac{9}{10}\)

b) \(\dfrac{39}{7}:x=13\)

\(x=\dfrac{\dfrac{39}{7}}{13}=\dfrac{3}{7}\)

c) \(\left(\dfrac{14}{5}x-50\right):\dfrac{2}{3}=51\)

\(\dfrac{14}{5}x-50=51\cdot\dfrac{2}{3}=34\)

\(\dfrac{14}{5}x=34+50=84\)

\(x=\dfrac{84}{\dfrac{14}{5}}=30\)

d) \(\left(x+\dfrac{1}{2}\right)\left(\dfrac{2}{3}-2x\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{2}=0\\\dfrac{2}{3}-2x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{1}{2}\\x=\dfrac{1}{3}\end{matrix}\right.\)

e) \(\dfrac{2}{3}x-\dfrac{1}{2}x=\dfrac{5}{12}\)

\(\dfrac{1}{6}x=\dfrac{5}{12}\)

\(x=\dfrac{5}{12}:\dfrac{1}{6}=\dfrac{5}{2}\)

g) \(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\dfrac{11}{5}-\dfrac{3}{7}=-2\)

\(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\cdot\dfrac{11}{5}=-2+\dfrac{3}{7}=-\dfrac{11}{7}\)

\(x\cdot\dfrac{44}{7}+\dfrac{3}{7}=-\dfrac{11}{7}:\dfrac{11}{5}=-\dfrac{5}{7}\)

\(\dfrac{44}{7}x=-\dfrac{5}{7}-\dfrac{3}{7}=-\dfrac{8}{7}\)

\(x=-\dfrac{8}{7}:\dfrac{44}{7}=-\dfrac{2}{11}\)

h) \(\dfrac{13}{4}x+\left(-\dfrac{7}{6}\right)x-\dfrac{5}{3}=\dfrac{5}{12}\)

\(\dfrac{25}{12}x-\dfrac{5}{3}=\dfrac{5}{12}\)

\(\dfrac{25}{12}x=\dfrac{5}{12}+\dfrac{5}{3}=\dfrac{25}{12}\)

\(x=1\)

Mỏi tay woa bn làm nốt nha!!

a) Ta có: \(3x-5+7x=17-2x+8\)

\(\Leftrightarrow10x-5=25-2x\)

\(\Leftrightarrow10x-5-25+2x=0\)

\(\Leftrightarrow12x-30=0\)

\(\Leftrightarrow12x=30\)

\(\Leftrightarrow x=\frac{30}{12}=\frac{5}{2}\)

Vậy: \(x=\frac{5}{2}\)

b) Ta có: \(13-5x+14=3x-17-9x\)

\(\Leftrightarrow27-5x=-17-6x\)

\(\Leftrightarrow27-5x+17+6x=0\)

\(\Leftrightarrow44+x=0\)

\(\Leftrightarrow x=-44\)

Vậy: x=-44

c) Ta có: \(x-12+4x=25+2x-49\)

\(\Leftrightarrow x-12+4x-25-2x+49=0\)

\(\Leftrightarrow3x+12=0\)

\(\Leftrightarrow x=-4\)

Vậy: x=-4

d) Ta có: \(7x+10+5=3\left(2x-3\right)-9x\)

\(\Leftrightarrow7x+15=6x-9-9x\)

\(\Leftrightarrow7x+15-6x+9+9x=0\)

\(\Leftrightarrow10x+24=0\)

\(\Leftrightarrow10x=-24\)

\(\Leftrightarrow x=-\frac{24}{10}=\frac{-12}{5}\)

Vậy: \(x=-\frac{12}{5}\)

22 tháng 7 2019

a) \(8-\left|3x-5\right|=-14\) 

\(\Rightarrow\left|3x-5\right|=22\)

\(\Rightarrow TH1:3x-5=22\Rightarrow x=9\)

\(TH2:3x-5=-22\Rightarrow x=\frac{-17}{3}\)  

Vậy......

mấy câu kia tương  tự 

5 tháng 8 2019

hhhhh

4 tháng 9 2018

x 3 - x - 1 3 4 x + 3 x - 5 = 7 x - 1 4 x + 3 - x x - 5         Đ K X Đ :   x ≠ - 3 4   v à   x ≠ 5 ⇔ x 3 - x - 1 3 4 x + 3 x - 5 = 7 x - 1 x - 5 4 x + 3 x - 5 - x 4 x + 3 4 x + 3 x - 5

⇔ x 3 - x - 1 3  = (7x – 1)(x – 5) – x(4x + 3)

⇔ x 3  –  x 3  + 3 x 2  – 3x + 1 = 7 x 2  – 35x – x + 5 – 4 x 2  – 3x

⇔ 3 x 2 – 7 x 2  + 4 x 2 – 3x + 35x + x + 3x = 5 – 1

⇔ 36x = 4 ⇔ x = 1/9 (thoả mãn)

Vậy phương trình có nghiệm x = 1/9

9 tháng 2 2021

a)  3x – 15 = 25 – 5x 

=> 3x + 5x = 25 + 15

=> 8x = 40

=> x = 5

 b) 3x - 17 = 2x – 7     

=> 3x - 2x = -7 + 17

=> x = 10

 c) 2x – 17 =  – (3x – 18)

=> 2x - 17 = -3x + 18

=> 2x + 3x = 18 + 17

=> 5x = 35

=> x = 7

d) 3x – 14 = 2(x – 9) + 1

=> 3x - 14 = 2x - 18 + 1

=> 3x - 2x = -18 + 1 + 14

=> x = -3

f) (x – 5)2 = 9          

\(\Rightarrow\left[{}\begin{matrix}x-5=3\\x-5=-3\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=8\\x=2\end{matrix}\right.\)

 

 

a) Ta có: \(3x-15=25-5x\)

\(\Leftrightarrow3x-15-25+5x=0\)

\(\Leftrightarrow8x-40=0\)

\(\Leftrightarrow8x=40\)

hay x=5

Vậy: x=5

b) Ta có: \(3x-17=2x-7\)

\(\Leftrightarrow3x-17-2x+7=0\)

\(\Leftrightarrow x-10=0\)

hay x=10

Vậy: x=10

c) Ta có: \(2x-17=-\left(3x-18\right)\)

\(\Leftrightarrow2x-17=-3x+18\)

\(\Leftrightarrow2x-17+3x-18=0\)

\(\Leftrightarrow5x-35=0\)

\(\Leftrightarrow5x=35\)

hay x=7

Vậy: x=7

d) Ta có: \(3x-14=2\left(x-9\right)+1\)

\(\Leftrightarrow3x-14=2x-18+1\)

\(\Leftrightarrow3x-14-2x+18-1=0\)

\(\Leftrightarrow x+3=0\)

\(\Leftrightarrow x=-3\)

Vậy: x=-3

f) Ta có: \(\left(x-5\right)^2=9\)

\(\Leftrightarrow\left[{}\begin{matrix}x-5=3\\x-5=-3\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=8\\x=2\end{matrix}\right.\)

Vậy: \(x\in\left\{2;8\right\}\)

Câu 1: 

a: =>-2x-x+17=34+x-25

=>-3x+17=x+9

=>-4x=-8

hay x=2

b: =>17x+16x+27=2x+43

=>33x+27=2x+43

=>31x=16

hay x=16/31

c: =>-2x-3x+51=34+2x-50

=>-5x+51=2x-16

=>-7x=-67

hay x=67/7

e: 3x-32>-5x+1

=>8x>33

hay x>33/8