(1/2-3/4) x - 7/3 = -5/9

-1/4 x  =16/9

x= -64/9

Bài 1:

a, \(\frac{1}{-16}-\frac{3}{45}=\frac{-1}{16}-\frac{1}{15}\)

\(=\frac{-15}{240}-\frac{16}{240}\)

\(=\frac{-31}{240}\)

b, \(=\frac{-10}{12}-\frac{-12}{12}\)

\(=\frac{2}{12}=\frac{1}{6}\)

c, \(=\frac{-30}{6}-\frac{1}{6}\)

\(=\frac{-31}{6}\)

Bài 2:

a, \(x=-\frac{1}{2}-\frac{3}{4}\)

\(x=-\frac{1}{4}\)

b,   \(\frac{1}{2}+x=-\frac{11}{2}\)

\(x=-\frac{11}{2}-\frac{1}{2}\)

\(x=-6\)

Bạn nhớ k đúng và chọn câu trả lời này nhé!!!! Mình giải đúng và chính xác hết ^_^

  Bài 1:  \(x\).(\(x-y\)) = \(\dfrac{3}{10}\) và y(\(x-y\)) = - \(\dfrac{3}{50}\)

    \(x\)(\(x\) - y) - y(\(x\) - y) = \(\dfrac{3}{10}\) - ( - \(\dfrac{3}{50}\))

     (\(x-y\)).(\(x-y\)) = \(\dfrac{3}{10}\) + \(\dfrac{3}{50}\)

        (\(x-y\))² = \(\dfrac{15}{50}\) + \(\dfrac{3}{50}\)

        (\(x\) - y)² = \(\dfrac{9}{25}\) = (\(\dfrac{3}{5}\))²

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

TH1 \(x-y=-\dfrac{3}{5}\) ⇒ \(\left\{{}\begin{matrix}x.\left(-\dfrac{3}{5}\right)=\dfrac{3}{10}\\y.\left(-\dfrac{3}{5}\right)=-\dfrac{3}{50}\end{matrix}\right.\) 

⇒ \(\left\{{}\begin{matrix}x=\dfrac{3}{10}:\left(-\dfrac{3}{5}\right)=\dfrac{-1}{2}\\y=-\dfrac{3}{50}:\left(-\dfrac{3}{5}\right)=\dfrac{1}{10}\end{matrix}\right.\) 

TH2: \(x-y=\dfrac{3}{5}\) ⇒ \(\left\{{}\begin{matrix}x.\dfrac{3}{5}=\dfrac{3}{10}\\y.\dfrac{3}{5}=-\dfrac{3}{50}\end{matrix}\right.\)

⇒ \(\left\{{}\begin{matrix}x=\dfrac{3}{10}:\dfrac{3}{5}=\dfrac{1}{2}\\y=-\dfrac{3}{50}:\dfrac{3}{5}=-\dfrac{1}{10}\end{matrix}\right.\)  

    Vậy (\(x;y\)  ) = (- \(\dfrac{1}{2}\); \(\dfrac{1}{10}\)); (\(\dfrac{1}{2}\); - \(\dfrac{1}{10}\))

\(1-\left(11\frac{1}{2}-10,1+x\right):8\frac{2}{5}=0\)

=>\(1-\left(\frac{21}{2}-\frac{101}{10}+x\right):\frac{42}{5}=0\)

=> \(1-\left(\frac{2}{5}+x\right)=0\)

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

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

=>\(x=\frac{3}{5}\)

Vậy ..................

\(\frac{x-5}{3}=\frac{6}{5}\)

\(x-5=\frac{6}{5}.3\)

\(x-5=\frac{18}{5}\)

\(x=\frac{18}{5}+5\)

\(\Rightarrow x=\frac{43}{5}\)

Vậy ...

\(\frac{1}{3}=\frac{2-x}{4}\)

\(\frac{4}{3}=2-x\)

\(x=2-\frac{4}{3}\)

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

Vậy ...

x - 5 = 6 * 3 / 5 => x - 5 = 3.6 => x = 8.6

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

a) \(\frac{x-5}{3}=\frac{6}{5}\)

5 . ( x - 5 ) = 6 . 3

5x - 25 = 18

5x        = 18 + 25

5x        = 43

  x        = 43 : 5 

  x        = 8,6

a) \(\frac{1}{3}=\frac{2-x}{4}\)

4 = 6 - 3x

6 - 4 = 3x

2 = 3x

x = 2 : 3 

x= \(\frac{2}{3}\)

Áp dụng tính chất dãy tỉ số bằng nhau, ta có:

\(\frac{x+1}{2}=\frac{y+3}{4}\)\(=\frac{z+5}{6}\)\(=\frac{2.\left(x+1\right)+3.\left(y+3\right)+4.\left(z+5\right)}{2.2+3.4+4.6}\)

\(=\frac{2x+2+3y+9+4z+20}{4+12+24}\)\(=\frac{\left(2x+3y+4z\right)+\left(2+9+20\right)}{40}\)

\(=\frac{9+31}{40}=\frac{40}{40}=1\)

Cứ thế là tìm x+1 rồi tìm x

                    y+3           y

                    x+5           z

\(\frac{2}{3}x-\frac{3}{2}\left(x-\frac{1}{2}\right)=\frac{5}{12}\)

\(\Rightarrow\frac{2}{3}x-\frac{3}{2}x+\frac{3}{4}=\frac{5}{12}\)

\(\Rightarrow\frac{-5}{6}x=\frac{5}{12}-\frac{3}{4}=\frac{-1}{3}\)

\(\Rightarrow x=\frac{-1}{3}:\frac{-5}{6}=\frac{2}{5}\)

vậy x = \(\frac{2}{5}\)

= 2/3x - 3/2x - 3/2 × 1/2= 5/12

=> -5/6x - 3/4 = 5/12

=> -5/6x = 5/12 +3/4= 7/6

=>x=7/6 ÷ -5/6 =1/3

TK MK NHA . CHÚC BẠN HỌC GIỎI

ĐÚNG 100% NHA

2/3x-3/2(x-1/2)=5/12

2/3x-3/2x+3/4=5/12

2/3x-3/2x=5/12-3/4

-5/6x=-1/3

x=2/5

giúp mik với

\(\frac{2-x}{x+3}=\frac{6}{5}\)

<=>\(5\left(2-x\right)=6\left(x+3\right)\)

<=>\(10-5x=6x+18\)

<=>\(\left(-5x\right)-6x=18-10\)

<=>\(-11x=8\)

<=>\(x=\frac{-8}{11}\)

cảm ơn bn