Các bạn cố gắng giúp mình nha . Mình xin chân thành cảm ơn 

2(1-2x)-5=3(x+2)

=>\(2-4x-5=3x+6\)

=>\(-4x-3=3x+6\)

=>\(-7x=9\)

=>\(x=-\dfrac{9}{7}\)

a) 2x - 3 = x + 1/2

<=> 2x - 3 = 1/2x + 1/2

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

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

<=> 3/2x = 1/2 + 3

<=> 3/2x = 7/2

<=> x = 7/2 : 3/2

<=> x = 7/3

=> x = 7/3

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

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

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

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

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

\(\frac{3}{2}x=\frac{7}{2}\)

\(x=\frac{7}{2}:\frac{3}{2}\)

\(x=\frac{14}{6}=\frac{7}{3}\)

\(\)B làm tương tự 

Bài làm:

Ta có: \(\left(2x-5\right)\left(x^3+1\right)-\left(2x-5\right)\left(x+1\right)=0\)

\(\Leftrightarrow\left(2x-5\right)\left(x+1\right)\left(x^2-x+1\right)-\left(2x-5\right)\left(x+1\right)=0\)

\(\Leftrightarrow\left(2x-5\right)\left(x+1\right)\left(x^2-x-1\right)=0\)

\(\Leftrightarrow x\left(x-1\right)\left(x+1\right)\left(2x-5\right)=0\)

GPT này ra ta được: \(x\in\left\{-1;0;1;\frac{5}{2}\right\}\)

\(\left(2x-5\right)\left(x^3+1\right)-\left(2x-5\right)\left(x+1\right)=0\)

\(\Leftrightarrow2x^4+2x-5x^3-5-\left(2x^2+2x-5x-5\right)=0\)

\(\Leftrightarrow2x^4+2x-5x^3-5-2x^2-2x+5x+5=0\)

\(\Leftrightarrow2x^4+5x-5x^3-2x^2=0\)

\(\Leftrightarrow x\left(2x^3+5-5x^2-2x\right)=0\)

\(\Leftrightarrow x=0;\frac{5}{2};\pm1\)

giúp mình với  :(((

|2x+1|=3-(-5)

|2x+1|=8

=>2x+1=8

hoặc 2x+1=-8

=>x=7/2

hoặc x=-9/2

vậy x=7/2 hoặc x=-9/2

\(3-\left|2x+1\right|=-5\)

\(\Leftrightarrow\left|2x+1\right|=8\)

\(\Leftrightarrow\orbr{\begin{cases}2x+1=8\\2x+1=-8\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}2x=7\\2x=-9\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=\frac{7}{2}\\x=\frac{-9}{2}\end{cases}}\)

Vậy\(x=\frac{7}{2}\)hoặc\(x=\frac{-9}{2}\)

Banh Bao Tong

giải dùm bn thoi chứ h mk k cần vì mk có kinh nghiem ke hứa nhieu

k bao gio giu loi hua

2x -3x +5x  = 3/3 - 4/4 + 12/5

4x = 1-1 + 12/5 

x = 3/5

\(\Leftrightarrow2x\left(x+5\right)-3\left(x-2\right)=7x+1\)

\(\Leftrightarrow2x^2+10x-3x+6-7x-1=0\)

\(\Leftrightarrow2x^2+5=0\)(vô lý)

ĐKXĐ:\(\left\{{}\begin{matrix}x\ne2\\x\ne-5\end{matrix}\right.\)

\(\dfrac{2x}{x-2}-\dfrac{3}{x+5}=\dfrac{7x+1}{x^2+3x-10}\\ \Leftrightarrow\dfrac{2x\left(x+5\right)}{\left(x+5\right)\left(x-2\right)}-\dfrac{3\left(x-2\right)}{\left(x+5\right)\left(x-2\right)}=\dfrac{7x+1}{x^2-2x+5x-10}\\ \Leftrightarrow\dfrac{2x^2+10x}{\left(x+5\right)\left(x-2\right)}-\dfrac{3x-6}{\left(x+5\right)\left(x-2\right)}=\dfrac{7x+1}{x\left(x-2\right)+5\left(x-2\right)}\\ \Leftrightarrow\dfrac{2x^2+10x}{\left(x+5\right)\left(x-2\right)}-\dfrac{3x-6}{\left(x+5\right)\left(x-2\right)}-\dfrac{7x+1}{\left(x+5\right)\left(x-2\right)}=0\)

\(\Leftrightarrow\dfrac{2x^2+10x-3x+6-7x-1}{\left(x+5\right)\left(x-2\right)}=0\\ \Leftrightarrow\dfrac{2x^2+5}{\left(x+5\right)\left(x-2\right)}=0\\ \Rightarrow2x^2+5=0\left(vô.lí\right)\)

Vậy pt vô nghiệm