`C=(12/35-6/7+18/14):6/(-7)-(-2)/5-1`

`C=(12/35-6/7+9/7):(-6)/7+2/5-1`

`C=(12/35+3/7):(-6)/7+2/5-1`

`C=(12/35+15/35):(-6)/7+2/5-1`

`C=27/35*(-7)/6+2/5-1`

`C=-9/10+2/5-1`

`C=-9/10+4/10-1`

`C=-1/2-1=-3/2`

Ta có: \(C=\left(\dfrac{12}{35}-\dfrac{6}{7}+\dfrac{18}{14}\right):\dfrac{6}{-7}-\dfrac{-2}{5}-1\)

\(=\left(\dfrac{24}{70}-\dfrac{60}{70}+\dfrac{90}{70}\right):\dfrac{-6}{7}-\dfrac{-2}{5}-\dfrac{5}{5}\)
\(=\dfrac{27}{35}\cdot\dfrac{-7}{6}-\dfrac{3}{5}\)

\(=\dfrac{-3}{2}\)

= -584/495 

hay ÂM 584 PHẦN 495 

sai thì thôi nha !!!

    \(\left(-\dfrac{5}{9}\right)+\dfrac{8}{18}+\left(-\dfrac{12}{11}\right)+\left(-\dfrac{4}{9}\right)+\dfrac{7}{15}\)
\(=\left[\dfrac{4}{9}+\left(-\dfrac{4}{9}\right)\right]+\left(-\dfrac{5}{9}\right)+\left(-\dfrac{12}{11}\right)+\dfrac{7}{15}\)
\(=-\dfrac{224}{495}\)

Nhầm rồi, kết quả là -(584/495) nhé.

\(a,\dfrac{6}{5}=\dfrac{18}{x}\\ \Rightarrow x=18:\dfrac{6}{5}\\ \Rightarrow x=15\\ b,\dfrac{3}{4}=\dfrac{-21}{x}\\ \Rightarrow x=-21:\dfrac{3}{4}\\ \Rightarrow x=-28\\ c,\dfrac{2}{-7}=\dfrac{18}{x}\\ \Rightarrow x=18:\dfrac{2}{-7}\\ \Rightarrow x=-63\\ d,\dfrac{-5}{2}=\dfrac{10}{-x}\\ \Rightarrow x=-10:\dfrac{-5}{2}\\ \Rightarrow x=4\)

\(a,\dfrac{6}{5}=\dfrac{18}{x}\Rightarrow6.x=5.18=90\\ \Rightarrow6.x=90\\ \Rightarrow x=15\\ b,\dfrac{3}{4}=\dfrac{-21}{x}\Rightarrow3.x=4.21=84\\ \Rightarrow x=28\)

\(a,\dfrac{6}{5}=\dfrac{18}{x}=>x=\dfrac{18.5}{6}=\dfrac{90}{6}=15\)

\(b,\dfrac{3}{4}=-\dfrac{21}{x}=>x=-\dfrac{21.4}{3}=-\dfrac{84}{3}=24\)

\(c,\dfrac{2}{-7}=\dfrac{18}{x}=>x=\dfrac{18.-7}{2}=-\dfrac{126}{2}=-63\)

\(d,-\dfrac{5}{2}=\dfrac{10}{-x}=>-x=\dfrac{10.2}{-5}=\dfrac{20}{-5}=-4=>x=4\)

bằng 19/44 nhá

tớ tính mãi mới ra

.......................................

19/44

\(\dfrac{43}{44}\)

- \(\dfrac{5}{11}\) = \(\dfrac{20}{x}\) = \(\dfrac{-35}{y}\)

  \(x\)   = 20 : (-\(\dfrac{5}{11}\)) 

  \(x\) = -44

y = - 35 : (- \(\dfrac{5}{11}\))

y = 77

D