`a)1/3x-1/4x=1`

`(1/3-1/4)x=1`

`1/12x=1`

`x=1:1/12=12`

______________________________

`b)4/5+5/7:x=1/6`

`5/7:x=1/6-4/5`

`5/7:x=-19/30`

`x=5/7:(-19/30)`

`x=-150/133`

__________________________________

`c)[2x]/3-x/4=5/6`

`x(2/3-1/4)=5/6`

`x. 5/12=5/6`

`x=5/6:5/12=2`

a) 1/3x - 1/4x = 1

1/12x = 1

x = 1 . 12

x = 12

b) 4/5 + 5/7: x = 1/6

5/7 : x = 1/6 - 4/5

5/7 : x = -19/30

x = 5/7 : -19/30

x = -150/133

c) 2x/3 - x/4 = 5/6

4 . 2x - 3x = 10

8x - 3x = 10

5x = 10

x = 10 : 5

x = 2.

b: =>2x^2-8x+3x-12+x^2-7x+10=3x^2-17x+20

=>-12x-2=-17x+20

=>5x=22

=>x=22/5

c: =>24x^2+16x-9x-6-4x^2-16x-7x-28=20x^2-4x+5x-1

=>-16x-34=x-1

=>-17x=33

=>x=-33/17

d: =>2x^2+3x^2-3=5x^2+5x

=>5x=-3

=>x=-3/5

e: =>8x+16-5x^2-10x+4x^2-4x-8=4-x^2

=>-6x+8=4

=>-6x=-4

=>x=2/3

f: =>4(x^2+4x-5)-x^2-7x-10=3x^2+3x-6

=>4x^2+16x-20-4x^2-10x+4=0

=>6x=16

=>x=8/3

nhiều quá :((

\(a,2\left(x-5\right)-3\left(x+7\right)=14\)

\(2x-10-3x-21=14\)

\(-x-31=14\)

\(-x=45\)

\(x=45\)

\(b,5\left(x-6\right)-2\left(x+3\right)=12\)

\(5x-30-2x-6=12\)

\(3x-36==12\)

\(3x=48\)

\(x=16\)

\(c,3\left(x-4\right)-\left(8-x\right)=12\)

\(3x-12-8+x=0\)

\(4x-20=0\)

\(4x=20\)

\(x=5\)

Cố nốt nha bn ! 

cảm ơn, bn nha:)))

mà hình như bạn TOP 3 trả lời câu hỏi pải ko nhỉ???

d, \(-7\left(3x-5\right)+2\left(7x-14\right)=28\)

\(\Leftrightarrow-21x+35+14x-28=28\Leftrightarrow-7x=21\Leftrightarrow x=-3\)

e, \(5\left(3-2x\right)+5\left(x-4\right)=6-4x\)

\(\Leftrightarrow15-6x+5x-20=6-4x\Leftrightarrow-5-x=6-4x\)

\(\Leftrightarrow-11+3x=0\Leftrightarrow x=\frac{11}{3}\)

f, \(-5\left(2-x\right)+4\left(x-3\right)=10x-15\)

\(\Leftrightarrow-10+5x+4x-12=10x-15\Leftrightarrow-22+9x=10x-15\)

\(\Leftrightarrow-7-x=0\Leftrightarrow x=-7\)

a) \(\left|\frac{3}{2}x+\frac{1}{2}\right|=\left|4x-1\right|\) 

\(\Rightarrow\orbr{\begin{cases}\frac{3}{2}x+\frac{1}{2}=4x-1\\\frac{3}{2}x+\frac{1}{2}=-4x+1\end{cases}}\Rightarrow\orbr{\begin{cases}4x-\frac{3}{2}x-1=\frac{1}{2}\\-4x-\frac{3}{2}x+1=\frac{1}{2}\end{cases}}\Rightarrow\orbr{\begin{cases}\frac{5}{2}x=\frac{3}{2}\\-\frac{11}{2}x=-\frac{1}{2}\end{cases}}\Rightarrow\orbr{\begin{cases}x=\frac{3}{5}\\x=\frac{1}{11}\end{cases}}\) 

phần b ở đề bài mình ghi sai, là bằng 0 chứ ko phải bằng 10

a: \(\Leftrightarrow\left(\dfrac{13}{4}:x\right)\cdot\left(-\dfrac{5}{4}\right)=\dfrac{-10}{6}-\dfrac{5}{6}=\dfrac{-15}{6}=\dfrac{-5}{2}\)

\(\Leftrightarrow\dfrac{13}{4}:x=\dfrac{5}{2}\cdot\dfrac{5}{4}=\dfrac{25}{8}\)

hay \(x=\dfrac{13}{4}:\dfrac{25}{8}=\dfrac{13}{4}\cdot\dfrac{8}{25}=\dfrac{26}{25}\)

b: \(\Leftrightarrow\dfrac{3}{4}:x=\dfrac{11}{36}-\dfrac{1}{4}=\dfrac{2}{36}=\dfrac{1}{18}\)

=>\(x=\dfrac{3}{4}:\dfrac{1}{18}=\dfrac{54}{4}=\dfrac{27}{2}\)

c: \(\Leftrightarrow\left(-\dfrac{6}{5}+x\right):\left(-3.6\right)=-\dfrac{7}{4}+\dfrac{1}{4}\cdot8=\dfrac{1}{4}\)

=>x-6/5=-9/10

=>x=3/10

Bạn nên viết đề bằng công thức toán và ghi đầy đủ yêu cầu đề để mọi người hiểu đề của bạn hơn nhé.

Lời giải:

a.

$\frac{-2}{3}+2x=\frac{4}{3}$

$2x=\frac{4}{3}-\frac{-2}{3}=2$

$x=2:2=1$

b.

$\frac{5}{8}-5:x=\frac{-3}{8}$

$5:x=\frac{5}{8}-\frac{-3}{8}=1$

$x=5:1=5$

c.

$\frac{2}{3}-x=\frac{-1}{2}$

$x=\frac{2}{3}-\frac{-1}{2}=\frac{7}{6}$

d.

$\frac{5}{7}-4x=\frac{-51}{7}$

$4x=\frac{5}{7}-\frac{-51}{7}=8$

$x=8:4=2$

a) \(-\dfrac{2}{3}+2x=\dfrac{4}{3}\)

\(\Rightarrow2x=\dfrac{4}{3}+\dfrac{2}{3}\)

\(\Rightarrow2x=2\)

\(\Rightarrow x=1\)

b) \(\dfrac{5}{8}-5:x=-\dfrac{3}{8}\)

\(\Rightarrow5:x=\dfrac{5}{8}+\dfrac{3}{8}\)

\(\Rightarrow5:x=1\)

\(\Rightarrow x=5\)

c) \(\dfrac{2}{3}-x=-\dfrac{1}{2}\)

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

\(\Rightarrow x=\dfrac{7}{6}\)

d) \(\dfrac{5}{7}-4x=-\dfrac{51}{7}\)

\(\Rightarrow4x=\dfrac{5}{7}+\dfrac{51}{7}\)

\(\Rightarrow4x=8\)

\(\Rightarrow x=2\)

`@` `\text {Ans}`

`\downarrow`

`a,`

`-2/3 + 2x = 4/3`

`=> 2x = 4/3 - (-2/3)`

`=> 2x = 2`

`=> x=2 \div 2`

`=> x=1`

Vậy, `x=1`

`b,`

`5/8 - 5 : x = -3/8`

`=> 5 \div x = 5/8 - (-3/8)`

`=> 5 \div x = 1`

`=> x= 5 \div 1`

`=> x=5`

Vậy, `x=5`

`c,`

`2/3 - x = -1/2`

`=> x=2/3 - (-1/2)`

`=> x=7/6`

Vậy, `x=7/6`

`d,`

`5/7 - 4x = -51/7`

`=> 4x = 5/7 - (-51/7)`

`=> 4x=8`

`=> x=8 \div 4`

`=> x=2`

Vậy, `x=2.`

`@` `\text {Kaizuu lv u}`