`2-3x = -1`
`3x =2-(-1)`
`3x = 2 + 1`
`3x=3`
`x=3:3`
`x=1`
Vậy `x = 1`
_______________________________
`x +2x+3x+4x-5x=16`
`(1+2+3+4-5).x = 16`
`5x = 16`
`=> x = 16 : 5`
`x=16/5`
Vậy `x = 16/5`
________________________________
`1/5 - x : 2/3 = 3/4`
`x : 2/3 = 1/5 - 3/4`
`x : 2/3 = 4/20 - 15/20`
`x : 2/3 = (-11)/20`
`x=(-11)/20xx2/3`
`x=(-11)/30`
______________________________
`(3x - 1/2) : 3 - 4 = 1/5`
`(3x - 1/2) : 3 = 1/5 + 4`
`(3x - 1/2) : 3 = 1/5 + 20/5`
`(3x - 1/2) : 3 = 21/5`
`3x - 1/2 =21/5 xx 3`
`3x -1/2= 63/5`
`3x = 63/5 + 1/2`
`3x=13,1`
`x = 13,1 : 3`
`x=131/30`
Vậy `x = 131/30`
a.3x=2-(-1)
3x=3
x=3:3
x=1
b.x.(2+3+4-5)=16
x.4=16
x=16:4
x=4
c.\(x:\dfrac{2}{3}=\dfrac{1}{5}-\dfrac{3}{4}\)
\(x:\dfrac{2}{3}=\dfrac{-11}{20}\)
\(x=\dfrac{-11}{20}.\dfrac{2}{3}\)
\(x=\dfrac{-11}{30}\)
d,\(\left(3.x-\dfrac{1}{2}\right):3=\dfrac{1}{5}+4\)
\(\left(3.x-\dfrac{1}{2}\right):3=\dfrac{21}{20}\)
\(3.x-\dfrac{1}{2}=\dfrac{21}{20}:3\)
\(3.x-\dfrac{1}{2}=\dfrac{7}{20}\)
\(3.x=\dfrac{7}{20}+\dfrac{1}{2}\)
\(3.x=\dfrac{17}{20}\)
\(x=\dfrac{17}{20}:3\)
\(x=\dfrac{17}{60}\)
