`1,(x+1/2) xx 2/3=-5/7`
`=> x+1/2= -5/7 : 2/3`
`=>x+1/2=-5/7 xx 3/2`
`=> x+1/2= -15/14`
`=>x=-15/14-1/2`
`=>x=-15/14 - 7/14`
`=>x= -22/14`
`=>x=-11/7`
__
`2,(9/5-x)+1/2=-2/3`
`=> 9/5 -x =-2/3 -1/2`
`=> 9/5 -x= -4/6 -3/6`
`=> 9/5-x= -7/6`
`=> x= 9/5- (-7/6)`
`=>x=9/5 + 7/6`
`=>x=89/30`
__
`3,(5/6 xx x)-2 1/2=-7/3`
`=> 5/6 xx x =-7/3 + 5/2`
`=> 5/6 xx x = -14/6 + 15/6`
`=> 5/6 xx x = 1/6`
`=>x=1/6:5/6`
`=>x=1/6 xx 6/5`
`=>x=6/30`
`=>x=1/5`
__
`4,(x- (-1)/3 )+3/4=-5/2`
`=> x+1/3=-5/2-3/4`
`=>x+1/3= -10/4-3/4`
`=>x+1/3= -13/4`
`=>x=-13/4-1/3`
`=>x=-43/12`
__
`5,(6/7 +x)-9/5=-2/10`
`=> 6/7 +x=-2/10+9/5`
`=>6/7+x=-2/10 + 18/10`
`=> 6/7 +x= 16/10`
`=>x= 8/5 -6/7`
`=>x=26/35`
__
`6,2 1/2` hay j vậy cậu nhỉ ?
__
`7,-9/10 -x=1/2 +(-7/5)`
`=> -9/10-x= 5/10 + (-14/10)`
`=> -9/10 -x= -9/10`
`=> x= -9/10 - (-9/10)`
`=>x= -9/10 + 9/10`
`=> x= 0`
\(1,\left(x+\dfrac{1}{2}\right).\dfrac{2}{3}=\dfrac{-5}{7}\)
\(x+\dfrac{1}{2}=\dfrac{-5}{7}:\dfrac{2}{3}\)
\(x+\dfrac{1}{2}=\dfrac{-5}{7}.\dfrac{3}{2}\)
\(x+\dfrac{1}{2}=\dfrac{-15}{14}\)
\(x=\dfrac{-15}{14}-\dfrac{1}{2}\)
\(x=\dfrac{-15}{14}+\dfrac{-7}{14}\)
\(x=\dfrac{-11}{7}\)
\(2,\left(\dfrac{9}{5}-x\right)+\dfrac{1}{2}=\dfrac{-2}{3}\)
\(\dfrac{9}{5}-x=\dfrac{-2}{3}-\dfrac{1}{2}\)
\(\dfrac{9}{5}-x=\dfrac{-4}{6}+\dfrac{-3}{6}\)
\(\dfrac{9}{5}-x=\dfrac{-7}{6}\)
\(x=\dfrac{9}{5}-\dfrac{-7}{6}\)
\(x=\dfrac{54}{30}-\dfrac{-35}{30}\)
\(x=\dfrac{19}{30}\)
\(3,\left(\dfrac{5}{6}.x\right)-2\dfrac{1}{2}=\dfrac{-7}{3}\)
\(\left(\dfrac{5}{6}.x\right)-\dfrac{5}{4}=-\dfrac{7}{3}\)
\(\dfrac{5}{6}.x=\dfrac{-7}{6}+\dfrac{5}{4}\)
\(\dfrac{5}{6}.x=\dfrac{-28}{24}+\dfrac{30}{24}\)
\(\dfrac{5}{6}.x=\dfrac{1}{12}\)
\(x=\dfrac{1}{12}:\dfrac{5}{6}\)
\(x=\dfrac{1}{12}.\dfrac{6}{5}\)
\(x=\dfrac{1}{10}\)
\(4,\left(x-\dfrac{-1}{3}\right)+\dfrac{3}{4}=-\dfrac{5}{2}\)
\(x-\dfrac{-1}{3}=\dfrac{-5}{2}-\dfrac{3}{4}\)
\(x-\dfrac{-1}{3}=\dfrac{-10}{4}+\dfrac{-3}{4}\)
\(x-\dfrac{-1}{3}=\dfrac{-13}{4}\)
\(x=\dfrac{-13}{4}+\dfrac{-1}{3}\)
\(x=\dfrac{-39}{12}+\dfrac{-4}{12}\)
\(x=\dfrac{-43}{12}\)
\(5,\left(\dfrac{6}{7}+x\right)-\dfrac{9}{5}=\dfrac{-2}{10}\)
\(\dfrac{6}{7}+x=\dfrac{-2}{10}+\dfrac{9}{5}\)
\(\dfrac{6}{7}+x=\dfrac{-2}{10}+\dfrac{18}{10}\)
\(\dfrac{6}{7}+x=\dfrac{8}{5}\)
\(x=\dfrac{8}{5}-\dfrac{6}{7}\)
\(x=\dfrac{56}{35}-\dfrac{30}{35}\)
\(x=\dfrac{26}{35}\)
