a) - 3x + 10 = 1
- 3x = 1 -10
- 3x = -9
x = (-9) : (-3)
x = 3
vậy x=...
b) 7/8 + x = 3/5
x = 3/5 - 7/8
x = -11/40
vậy x=...
c) 1/3 : (2x - 1) = -4/21
2x - 1 = 1/3 : -4/21
2x - 1 = -7/4
2x = -7/4 + 1
2x = -3/4
x = -3/4 : 2
x = -3/8
vậy x =...
a) \(-3x+10=1\)
\(\Leftrightarrow-3x=-9\)
\(\Leftrightarrow x=3\)
Vậy x = 3
b) \(\dfrac{7}{8}+x=\dfrac{3}{5}\)
\(\Leftrightarrow x=\dfrac{3}{5}-\dfrac{7}{8}\)
\(\Leftrightarrow x=\dfrac{-11}{40}\)
Vậy \(x=\dfrac{-11}{40}\)
c) \(\dfrac{1}{3}:\left(2x-1\right)=\dfrac{-4}{21}\)
\(\Leftrightarrow2x-1=\dfrac{-7}{4}\)
\(\Leftrightarrow2x=\dfrac{-3}{4}\)
\(\Leftrightarrow x=\dfrac{-3}{8}\)
Vậy \(x=\dfrac{-3}{8}\)
d) \(\dfrac{17}{2}-\left|x-\dfrac{3}{4}\right|=\dfrac{-7}{4}\)
\(\Leftrightarrow\left|x-\dfrac{3}{4}\right|=\dfrac{41}{4}\)
\(\Leftrightarrow\left[{}\begin{matrix}x-\dfrac{3}{4}=\dfrac{41}{4}\\x-\dfrac{3}{4}=\dfrac{-41}{4}\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=11\\x=\dfrac{-19}{2}\end{matrix}\right.\)
Vậy \(x_1=11;x_2=\dfrac{-19}{2}\)
