a) \(\frac{3}{7}x-\frac{1}{35}=\frac{3}{5}\)
\(\frac{3}{7}x=\frac{3}{5}+\frac{1}{35}\)
\(\frac{3}{7}x=\frac{22}{35}\)
\(x=\frac{49}{35}=1,4\)
b) \(1,5-x:\frac{1}{2}=\frac{1}{4}\)
\(x:\frac{1}{2}=1,5-\frac{1}{4}\)
\(x:\frac{1}{2}=\frac{5}{4}\)
\(x=\frac{5}{4}.\frac{1}{2}\)
\(x=\frac{5}{8}\)
Vậy ..
a.\(\frac{3}{7}.x-\frac{1}{35}=\frac{3}{5}\)
\(\frac{3}{7}.x=\frac{3}{5}+\frac{1}{35}\)
\(\frac{3}{7}.x=\frac{11}{35}\)
\(x=\frac{22}{35}+\frac{3}{7}\)
\(x=\frac{37}{35}\)
a. \(1,5-x:\frac{1}{2}=\frac{1}{4}\)
\(x:\frac{1}{2}=1,5-\frac{1}{4}\)
\(x:\frac{1}{2}=\frac{5}{4}\)
\(x=\frac{5}{4}.\frac{1}{2}\)
\(x=\frac{5}{8}\)
c) 3x - 5 = 7 ( 2x - 1 ) + 3
<=> 3x - 5 = 14x - 7 + 3
<=> 3x - 14x = -7 + 3 + 5
<=> -11x = 1
<=> x = -1/11
Vậy ...
d) \(7-\left|3x-1\right|=\frac{1}{2}\)
\(\left|3x-1\right|=\frac{13}{2}\)
\(\Leftrightarrow\orbr{\begin{cases}3x-1=\frac{13}{2}\\3x-1=\frac{-13}{2}\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}3x=\frac{15}{2}\\3x=\frac{-11}{2}\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=\frac{5}{6}\\x=\frac{-11}{6}\end{cases}}\)
a, 3/7.x - 1/35 = 3/5
3/7.x = 3/5 + 1/35
3/7.x = 21/35 + 1/35
3/7.x = 22/35
x = 22/35 : 3/7
x = 22/35 . 7/3
x = 22/15
Vậy x = 22/15
b, 1,5 - x : 1/2 = 1/4
x : 1/2 = 1,5 - 1/4
x . 1/2 = 3/2 - 1/4
x . 1/2 = 6/4 - 1/4
x . 1/2 = 5/4
x = 5/4 : 1/2
x = 5/4 . 2
x = 5/2
Vậy x = 5/2
d, 7 - |3x -1| = 1/2
|3x -1| = 7 - 1/2
|3x -1| = 14/2 - 1/2
|3x -1| = 13/2
Suy ra 3x -1 = 13/2 hoặc 3x - 1 = -13/2
--Nếu 3x -1 = 13/2
3x = 13/2 + 1
3x = 15/2
x = 15/2 : 3
x = 15/2 . 1/3
x = 5/2
--Nếu 3x - 1 = -13/2
3x = -13/2 + 1
3x = -13/2 + 2/2
3x = -11/2
x = -11/2 : 3
x = -11/2 . 1/3
x = -11/6
Vậy x = 5/x; x = -11/6
