K
Khách

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

6 tháng 6 2018

a)

   \(\frac{2}{3}+\frac{1}{3}:x=\frac{3}{5}\)

   \(\frac{1}{3}:x=\frac{3}{5}-\frac{2}{3}\)

    \(\frac{1}{3}:x=\frac{-1}{15}\)

     \(x=\frac{1}{3}:\frac{-1}{15}\)

    \(x=-5\)

b)

     \(\frac{10}{3x}+\frac{67}{4}=-13.25\)

      \(\frac{10}{3x}+\frac{67}{4}=\frac{-53}{4}\)

       \(\frac{10}{3x}=\frac{-53}{4}+\frac{67}{4}\)

       \(\frac{10}{3x}=\frac{7}{2}\)

      \(\Rightarrow10.2=7.3x\)

            \(20=21x\)

            \(x=\frac{20}{21}\)

c)

        x+30%x=-1.3

        x+0.3x=-1.3

        x (1+0.3) = -1.3

        x . 1.3 = -1.3

        x = -1.3 : 1.3

        x = 1

d)

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

           \(\frac{14}{5x}-50=51.\frac{2}{3}\)

             \(\frac{14}{5x}-50=34\)

             \(\frac{14}{5x}=34+50\)

              \(\frac{14}{5x}=84\)

               \(84.5x=14\)

              420x = 14

                   \(x=\frac{1}{30}\)

   

6 tháng 6 2018

a, \(\frac{2}{3}+\frac{1}{3}:x=\frac{3}{5}\)

=> \(\frac{1}{3}:x=\frac{3}{5}-\frac{2}{3}\)

=>\(\frac{1}{3}:x=\frac{-1}{15}\)

=> \(x=\frac{1}{3}:\frac{-1}{15}\)

=> \(x=\frac{-1}{5}\)

22 tháng 3 2020

Mình trả lời câu b cho bạn nhé 

2[x+7]-3[x-2]=-2

2x-14-3*x+6=-2

2x-3x-14+6=-2

-x-14+6=-2

-x-14=-2-6

-x-14=-8

-x=-8+14

-x=6

<=>x=-6

4 tháng 5 2016

a) x+30%x=-1.31

=> 100%x+30%x=-1.31

=>x.(100%+30%)=-1.31

=>x.13/10=-1.31=-1.31:13/10=-131/130

b) (x-1/2):1/3+5/7=9+5/7

=>(x-1/2).3+5/7=68/7

=>(x-1/2).3=68/7-5/7=9

=>x-1/2=9:3=3

=>x=3+1/2=3 1/2( hỗn số)

c) 1/2x-3/4=14/9.3/7

=>1/2x-3/4=2/3

=>1/2x=2/3+3/4=17/12

x=17/12:1/2=17/12.2=17/6

d) - 5/6 -x = 7/12+ -1/3

=>- 5/6 -x = 7/12+ -4/12=1/4

=> x = -5/6 -1/4=-13/12

e) x + 3/-15 = 1/3

=> x= 1/3 - -3/15 =1/3+3/15

=> x=5/15 + 3/15=8/15

f) (4,5 -2 x). (-1 4/7)=11/14

=> 4,5 -2x=11/14 : -3/7=11/14. -7/3=-11/6

=>-2x=-11/6-9/2= -11/6 -27/6 =-19/3

=>x= -19/3: -2x=19/6

Chúc bn thi HKII tốt!!!

1 tháng 2 2017

ban hoc truong nao vay ? de cua ban giong cua minh lam

17 tháng 2 2020

d) |2x – 5| –7 = 22

| 2x -5 | = 22+7

| 2x -5 | = 29

TH1: 2x-5 = -29

2x = -29+5

2x= -24

x= -24:2

x= -12

TH2: 2x -5 =29

2x = 29+5

2x= 34

x= 34:2

x= 17 

Vậy...

17 tháng 2 2020

a) x – 14 = 3x + 18

x -14 - 3x = 18

-2x -14 =18

-2x = 18-14

-2x = 4

x = 4:( -2) 

x= -2

Vậy...

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 ! 

19 tháng 3 2020

cảm ơn, bn nha:)))

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

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!!