1/3x + 2/5 . ( x  - 1 ) = 0

1/3x + 2/5x - 2/5 . 1 = 0

x . ( 1/3 + 2/5 ) - 2/5 = 0

x . 11/15 = 0 + 2/5

x . 11/15 = 2/5

x = 2/5 : 11/15

x = 6/11

                   #Louis

( 2x - 3 )(6 - 2x ) = 0

=> 2x - 3 = 0 , 6 - 2x = 0

+) 2x - 3 = 0

     2x = 0 + 3

     2x = 3

       x = 3/2

+) 6 - 2x = 0

         2x = 6 + 0

         2x = 6

           x = 6 : 2 = 3

             Vậy...

                          #Hoq chắc _ Louis

a) <=> 15-5x-20=-12-3

<=> -5x=-12-3-15+20=-10

=>x=-10:(-5)=2

b)<=>7-x-25-7=-25

<=> -x=-25-7+25+7=0 =>x=0

c) /x+2/=0 => x+2=0 =>x=-2

d) sai đề

e)<=> /x-5/ = 7

<=> \(\orbr{\begin{cases}x-5=7\\x-5=-7\end{cases}}\)

<=> \(\orbr{\begin{cases}x=12\\x=-2\end{cases}}\)

g) <=> -x-20-8+2x=-15

<=> x=-15+20+8=13

d là | x + 3 | = 7 - ( - 2 )

M.N mau len ho minh voi!!

\(3^2x-4-x^0=8\)

9x-4-1=8

9x-5=8

9x=13

=>x=\(\frac{13}{9}\)

\(a,\left(2x-10\right)\left(x+3\right)=0\)

\(\Leftrightarrow\orbr{\begin{cases}2x-10=0\\x+3=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=5\\x=-3\end{cases}}\)

Vậy .........

\(b,\left(x+5\right)\left(x^2-9\right)=0\)

\(\Leftrightarrow\orbr{\begin{cases}x+5=0\\x^2-9=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=-5\\x=3\end{cases}}\)

Vậy ......

\(a,\left(2x-10\right)\left(x+3\right)=0\)

\(\Rightarrow\orbr{\begin{cases}2x-10=0\\x+3=0\end{cases}\Rightarrow\orbr{\begin{cases}2x=10\\x=-3\end{cases}\Rightarrow}\orbr{\begin{cases}x=5\\x=-3\end{cases}}}\)

\(b,\left(x+5\right)\left(x^2-9\right)=0\)

\(\Rightarrow\orbr{\begin{cases}x+5=0\\x^2-9=0\end{cases}\Rightarrow\orbr{\begin{cases}x=-5\\x^2=9\end{cases}\Rightarrow}\orbr{\begin{cases}x=-5\\x=3or-3\end{cases}}}\)

a) -45:5(-3-2x)=3

5(-3-2x)=-45:3

5(-3-2x)=-15

-3-2x=-15:5

-3-2x=-3

2x=(-3)-(-3)

2x=-6

x=-6:2

x=-3

a,Để \(|2x+1|+|x-2|=0\Leftrightarrow\hept{\begin{cases}2x+1=0\\x-2=0\end{cases}}\)(vô lý)

=> ko có x thỏa mãn

b,\(|x+5|=2x-1\Leftrightarrow1-2x< x+5< 2x-1\)

giai gium mik cau c 

a: =>|2x-4|=-2x+4

=>2x-4<=0

=>x<=2

b: =>|x+5|=x+5

=>x+5>=0

hay x>=-5

c: =>|x-2|=x-2

=>x-2>=0

hay x>=2